Tandem cyclisations involving α-ketenyl alkyl radicals. New syntheses of the natural triquinanes pentalenene and modhephene

Organic and Biomolecular Chemistry

Volumn 3, Issue 2, 2005, Pages 340-347

  De Boeck, Benoît ^a   Harrington Frost, Nicole M ^a   Pattenden, Gerald ^a  

^a UNIVERSITY OF NOTTINGHAM   (United Kingdom)

Author keywords

[No Author keywords available]

Indexed keywords

ACETIC ACID; CARBOXYLIC ACIDS; DEHYDRATION; ISOMERS; NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY; SYNTHESIS (CHEMICAL);

CYCLIZATION REACTIONS; MODHEPHENE; NATURAL TRIQUINANES;

AROMATIC HYDROCARBONS;

BRIDGED COMPOUND; CYCLOPENTANE DERIVATIVE; ETHYLENE DERIVATIVE; FREE RADICAL; KETENE; KETONE; MODHEPHENE; PENTALENENE; SESQUITERPENE;

ARTICLE; CHEMISTRY; CONFORMATION; CYCLIZATION; STEREOISOMERISM; SYNTHESIS;

BRIDGED COMPOUNDS; CYCLIZATION; CYCLOPENTANES; ETHYLENES; FREE RADICALS; KETONES; MOLECULAR CONFORMATION; SESQUITERPENES; STEREOISOMERISM;

EID: 12844257505     PISSN: 14770520     EISSN: None     Source Type: Journal    
DOI: 10.1039/b413817c     Document Type: Article

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4. See for example:L. Fevig, R. L. Elliott and D. P. Curran, J. Am. Chem. Soc., 1988, 110, 5064-5067; S. Danishefsky, R. Zamboni, M. Kahn and S. J. Etheredge, J. Am. Chem. Soc., 1981, 102, 3460-3467: S. Danishefsky, R. Zamboni, M. Kahn and S. J. Etheredge, J. Am. Chem. Sac., 1980, 102, 2097-2098; K. Tatsuta, K. Akimoto and M. Kinoshita, J. Antibiotics, 1980, 33, 100-102; R. D. Little and G. W. Muller, J. Am. Chem. Soc., 1981, 103, 2744-2749; R. D. Little and G. L. Carroll, Tetrahedron Lett., 1981, 22, 4389-4392; L. Van Hijfte, R. D. Little, J. L. Petersen and K. D. Moeller, J. Org. Chem., 1987, 52. 4647-4661; see also ref. 13 below.
5. See for example:L. Fevig, R. L. Elliott and D. P. Curran, J. Am. Chem. Soc., 1988, 110, 5064-5067; S. Danishefsky, R. Zamboni, M. Kahn and S. J. Etheredge, J. Am. Chem. Soc., 1981, 102, 3460-3467: S. Danishefsky, R. Zamboni, M. Kahn and S. J. Etheredge, J. Am. Chem. Sac., 1980, 102, 2097-2098; K. Tatsuta, K. Akimoto and M. Kinoshita, J. Antibiotics, 1980, 33, 100-102; R. D. Little and G. W. Muller, J. Am. Chem. Soc., 1981, 103, 2744-2749; R. D. Little and G. L. Carroll, Tetrahedron Lett., 1981, 22, 4389-4392; L. Van Hijfte, R. D. Little, J. L. Petersen and K. D. Moeller, J. Org. Chem., 1987, 52. 4647-4661; see also ref. 13 below.
6. See for example:L. Fevig, R. L. Elliott and D. P. Curran, J. Am. Chem. Soc., 1988, 110, 5064-5067; S. Danishefsky, R. Zamboni, M. Kahn and S. J. Etheredge, J. Am. Chem. Soc., 1981, 102, 3460-3467: S. Danishefsky, R. Zamboni, M. Kahn and S. J. Etheredge, J. Am. Chem. Sac., 1980, 102, 2097-2098; K. Tatsuta, K. Akimoto and M. Kinoshita, J. Antibiotics, 1980, 33, 100-102; R. D. Little and G. W. Muller, J. Am. Chem. Soc., 1981, 103, 2744-2749; R. D. Little and G. L. Carroll, Tetrahedron Lett., 1981, 22, 4389-4392; L. Van Hijfte, R. D. Little, J. L. Petersen and K. D. Moeller, J. Org. Chem., 1987, 52. 4647-4661; see also ref. 13 below.
7. See for example:L. Fevig, R. L. Elliott and D. P. Curran, J. Am. Chem. Soc., 1988, 110, 5064-5067; S. Danishefsky, R. Zamboni, M. Kahn and S. J. Etheredge, J. Am. Chem. Soc., 1981, 102, 3460-3467: S. Danishefsky, R. Zamboni, M. Kahn and S. J. Etheredge, J. Am. Chem. Sac., 1980, 102, 2097-2098; K. Tatsuta, K. Akimoto and M. Kinoshita, J. Antibiotics, 1980, 33, 100-102; R. D. Little and G. W. Muller, J. Am. Chem. Soc., 1981, 103, 2744-2749; R. D. Little and G. L. Carroll, Tetrahedron Lett., 1981, 22, 4389-4392; L. Van Hijfte, R. D. Little, J. L. Petersen and K. D. Moeller, J. Org. Chem., 1987, 52. 4647-4661; see also ref. 13 below.
8. See for example:L. Fevig, R. L. Elliott and D. P. Curran, J. Am. Chem. Soc., 1988, 110, 5064-5067; S. Danishefsky, R. Zamboni, M. Kahn and S. J. Etheredge, J. Am. Chem. Soc., 1981, 102, 3460-3467: S. Danishefsky, R. Zamboni, M. Kahn and S. J. Etheredge, J. Am. Chem. Sac., 1980, 102, 2097-2098; K. Tatsuta, K. Akimoto and M. Kinoshita, J. Antibiotics, 1980, 33, 100-102; R. D. Little and G. W. Muller, J. Am. Chem. Soc., 1981, 103, 2744-2749; R. D. Little and G. L. Carroll, Tetrahedron Lett., 1981, 22, 4389-4392; L. Van Hijfte, R. D. Little, J. L. Petersen and K. D. Moeller, J. Org. Chem., 1987, 52. 4647-4661; see also ref. 13 below.
9. See for example:L. Fevig, R. L. Elliott and D. P. Curran, J. Am. Chem. Soc., 1988, 110, 5064-5067; S. Danishefsky, R. Zamboni, M. Kahn and S. J. Etheredge, J. Am. Chem. Soc., 1981, 102, 3460-3467: S. Danishefsky, R. Zamboni, M. Kahn and S. J. Etheredge, J. Am. Chem. Sac., 1980, 102, 2097-2098; K. Tatsuta, K. Akimoto and M. Kinoshita, J. Antibiotics, 1980, 33, 100-102; R. D. Little and G. W. Muller, J. Am. Chem. Soc., 1981, 103, 2744-2749; R. D. Little and G. L. Carroll, Tetrahedron Lett., 1981, 22, 4389-4392; L. Van Hijfte, R. D. Little, J. L. Petersen and K. D. Moeller, J. Org. Chem., 1987, 52. 4647-4661; see also ref. 13 below.
10. See for example: D. P. Curran and D. M. Rakiewicz, J. Am. Chem. Soc., 1985, 107, 1448-1449; D. P. Curran and D. M. Rakiewicz, Tetrahedron. 1985, 41, 3943-3958; D. P. Curran and M.-H. Chen, Tetrahedron Lett., 1985, 26, 4991-4994; K. Weinges, H. Reichert, U. Huber-Patz and H. Irngartinger, Liebigs Ann. Chem., 1993, 26, 403-411; D. P. Curran and S.-C. Kuo, J. Am. Chem. Soc., 1986, 108, 1106-1107; D. P. Curran and S.-C. Kuo, Tetrahedron, 1987, 43, 5653-5661; Y. K. Rao and M. Nagarajan, Tetrahedron Lett., 1988, 29, 107-108; Y. K. Rao and M. Nagarajan, J. Org. Chem., 1989, 54, 5678-5683. For modhephene see:; C.-K. Sha, T.-S. Jean, N.-T. Yau, S.-J. Huang, R.-T. Chiou, J.-F. Young, S.-H. Lih and W.-H. Tseng, J. Chinese Chem. Soc., 1995, 42, 637-640; C.-K. Sha, T.-S. Jean and D.-C. Wang, Tetrahedron Lett., 1990, 31, 3745-3748; C. P. Jasperse and D. P. Curran, J. Am. Chem. Soc., 1990, 112, 5601-5609; D. P. Curran and W. Shen, Tetrahedron, 1993, 49, 755-770; S. Kim, I. S. Kee and S. Lee, J. Am. Chem. Soc., 1991, 113, 9882-9883; H.-Y. Lee, D.-I. Kim and S. Kim, Bull. Korean Chem. Soc., 1999, 20, 269-270; H-Y. Lee, D.-I. Kim and S. Kim, Chem. Commun., 1996, 20, 1539-1540.
11. See for example: D. P. Curran and D. M. Rakiewicz, J. Am. Chem. Soc., 1985, 107, 1448-1449; D. P. Curran and D. M. Rakiewicz, Tetrahedron. 1985, 41, 3943-3958; D. P. Curran and M.-H. Chen, Tetrahedron Lett., 1985, 26, 4991-4994; K. Weinges, H. Reichert, U. Huber-Patz and H. Irngartinger, Liebigs Ann. Chem., 1993, 26, 403-411; D. P. Curran and S.-C. Kuo, J. Am. Chem. Soc., 1986, 108, 1106-1107; D. P. Curran and S.-C. Kuo, Tetrahedron, 1987, 43, 5653-5661; Y. K. Rao and M. Nagarajan, Tetrahedron Lett., 1988, 29, 107-108; Y. K. Rao and M. Nagarajan, J. Org. Chem., 1989, 54, 5678-5683. For modhephene see:; C.-K. Sha, T.-S. Jean, N.-T. Yau, S.-J. Huang, R.-T. Chiou, J.-F. Young, S.-H. Lih and W.-H. Tseng, J. Chinese Chem. Soc., 1995, 42, 637-640; C.-K. Sha, T.-S. Jean and D.-C. Wang, Tetrahedron Lett., 1990, 31, 3745-3748; C. P. Jasperse and D. P. Curran, J. Am. Chem. Soc., 1990, 112, 5601-5609; D. P. Curran and W. Shen, Tetrahedron, 1993, 49, 755-770; S. Kim, I. S. Kee and S. Lee, J. Am. Chem. Soc., 1991, 113, 9882-9883; H.-Y. Lee, D.-I. Kim and S. Kim, Bull. Korean Chem. Soc., 1999, 20, 269-270; H-Y. Lee, D.-I. Kim and S. Kim, Chem. Commun., 1996, 20, 1539-1540.
12. See for example: D. P. Curran and D. M. Rakiewicz, J. Am. Chem. Soc., 1985, 107, 1448-1449; D. P. Curran and D. M. Rakiewicz, Tetrahedron. 1985, 41, 3943-3958; D. P. Curran and M.-H. Chen, Tetrahedron Lett., 1985, 26, 4991-4994; K. Weinges, H. Reichert, U. Huber-Patz and H. Irngartinger, Liebigs Ann. Chem., 1993, 26, 403-411; D. P. Curran and S.-C. Kuo, J. Am. Chem. Soc., 1986, 108, 1106-1107; D. P. Curran and S.-C. Kuo, Tetrahedron, 1987, 43, 5653-5661; Y. K. Rao and M. Nagarajan, Tetrahedron Lett., 1988, 29, 107-108; Y. K. Rao and M. Nagarajan, J. Org. Chem., 1989, 54, 5678-5683. For modhephene see:; C.-K. Sha, T.-S. Jean, N.-T. Yau, S.-J. Huang, R.-T. Chiou, J.-F. Young, S.-H. Lih and W.-H. Tseng, J. Chinese Chem. Soc., 1995, 42, 637-640; C.-K. Sha, T.-S. Jean and D.-C. Wang, Tetrahedron Lett., 1990, 31, 3745-3748; C. P. Jasperse and D. P. Curran, J. Am. Chem. Soc., 1990, 112, 5601-5609; D. P. Curran and W. Shen, Tetrahedron, 1993, 49, 755-770; S. Kim, I. S. Kee and S. Lee, J. Am. Chem. Soc., 1991, 113, 9882-9883; H.-Y. Lee, D.-I. Kim and S. Kim, Bull. Korean Chem. Soc., 1999, 20, 269-270; H-Y. Lee, D.-I. Kim and S. Kim, Chem. Commun., 1996, 20, 1539-1540.
13. See for example: D. P. Curran and D. M. Rakiewicz, J. Am. Chem. Soc., 1985, 107, 1448-1449; D. P. Curran and D. M. Rakiewicz, Tetrahedron. 1985, 41, 3943-3958; D. P. Curran and M.-H. Chen, Tetrahedron Lett., 1985, 26, 4991-4994; K. Weinges, H. Reichert, U. Huber-Patz and H. Irngartinger, Liebigs Ann. Chem., 1993, 26, 403-411; D. P. Curran and S.-C. Kuo, J. Am. Chem. Soc., 1986, 108, 1106-1107; D. P. Curran and S.-C. Kuo, Tetrahedron, 1987, 43, 5653-5661; Y. K. Rao and M. Nagarajan, Tetrahedron Lett., 1988, 29, 107-108; Y. K. Rao and M. Nagarajan, J. Org. Chem., 1989, 54, 5678-5683. For modhephene see:; C.-K. Sha, T.-S. Jean, N.-T. Yau, S.-J. Huang, R.-T. Chiou, J.-F. Young, S.-H. Lih and W.-H. Tseng, J. Chinese Chem. Soc., 1995, 42, 637-640; C.-K. Sha, T.-S. Jean and D.-C. Wang, Tetrahedron Lett., 1990, 31, 3745-3748; C. P. Jasperse and D. P. Curran, J. Am. Chem. Soc., 1990, 112, 5601-5609; D. P. Curran and W. Shen, Tetrahedron, 1993, 49, 755-770; S. Kim, I. S. Kee and S. Lee, J. Am. Chem. Soc., 1991, 113, 9882-9883; H.-Y. Lee, D.-I. Kim and S. Kim, Bull. Korean Chem. Soc., 1999, 20, 269-270; H-Y. Lee, D.-I. Kim and S. Kim, Chem. Commun., 1996, 20, 1539-1540.
14. See for example: D. P. Curran and D. M. Rakiewicz, J. Am. Chem. Soc., 1985, 107, 1448-1449; D. P. Curran and D. M. Rakiewicz, Tetrahedron. 1985, 41, 3943-3958; D. P. Curran and M.-H. Chen, Tetrahedron Lett., 1985, 26, 4991-4994; K. Weinges, H. Reichert, U. Huber-Patz and H. Irngartinger, Liebigs Ann. Chem., 1993, 26, 403-411; D. P. Curran and S.-C. Kuo, J. Am. Chem. Soc., 1986, 108, 1106-1107; D. P. Curran and S.-C. Kuo, Tetrahedron, 1987, 43, 5653-5661; Y. K. Rao and M. Nagarajan, Tetrahedron Lett., 1988, 29, 107-108; Y. K. Rao and M. Nagarajan, J. Org. Chem., 1989, 54, 5678-5683. For modhephene see:; C.-K. Sha, T.-S. Jean, N.-T. Yau, S.-J. Huang, R.-T. Chiou, J.-F. Young, S.-H. Lih and W.-H. Tseng, J. Chinese Chem. Soc., 1995, 42, 637-640; C.-K. Sha, T.-S. Jean and D.-C. Wang, Tetrahedron Lett., 1990, 31, 3745-3748; C. P. Jasperse and D. P. Curran, J. Am. Chem. Soc., 1990, 112, 5601-5609; D. P. Curran and W. Shen, Tetrahedron, 1993, 49, 755-770; S. Kim, I. S. Kee and S. Lee, J. Am. Chem. Soc., 1991, 113, 9882-9883; H.-Y. Lee, D.-I. Kim and S. Kim, Bull. Korean Chem. Soc., 1999, 20, 269-270; H-Y. Lee, D.-I. Kim and S. Kim, Chem. Commun., 1996, 20, 1539-1540.
15. See for example: D. P. Curran and D. M. Rakiewicz, J. Am. Chem. Soc., 1985, 107, 1448-1449; D. P. Curran and D. M. Rakiewicz, Tetrahedron. 1985, 41, 3943-3958; D. P. Curran and M.-H. Chen, Tetrahedron Lett., 1985, 26, 4991-4994; K. Weinges, H. Reichert, U. Huber-Patz and H. Irngartinger, Liebigs Ann. Chem., 1993, 26, 403-411; D. P. Curran and S.-C. Kuo, J. Am. Chem. Soc., 1986, 108, 1106-1107; D. P. Curran and S.-C. Kuo, Tetrahedron, 1987, 43, 5653-5661; Y. K. Rao and M. Nagarajan, Tetrahedron Lett., 1988, 29, 107-108; Y. K. Rao and M. Nagarajan, J. Org. Chem., 1989, 54, 5678-5683. For modhephene see:; C.-K. Sha, T.-S. Jean, N.-T. Yau, S.-J. Huang, R.-T. Chiou, J.-F. Young, S.-H. Lih and W.-H. Tseng, J. Chinese Chem. Soc., 1995, 42, 637-640; C.-K. Sha, T.-S. Jean and D.-C. Wang, Tetrahedron Lett., 1990, 31, 3745-3748; C. P. Jasperse and D. P. Curran, J. Am. Chem. Soc., 1990, 112, 5601-5609; D. P. Curran and W. Shen, Tetrahedron, 1993, 49, 755-770; S. Kim, I. S. Kee and S. Lee, J. Am. Chem. Soc., 1991, 113, 9882-9883; H.-Y. Lee, D.-I. Kim and S. Kim, Bull. Korean Chem. Soc., 1999, 20, 269-270; H-Y. Lee, D.-I. Kim and S. Kim, Chem. Commun., 1996, 20, 1539-1540.
16. See for example: D. P. Curran and D. M. Rakiewicz, J. Am. Chem. Soc., 1985, 107, 1448-1449; D. P. Curran and D. M. Rakiewicz, Tetrahedron. 1985, 41, 3943-3958; D. P. Curran and M.-H. Chen, Tetrahedron Lett., 1985, 26, 4991-4994; K. Weinges, H. Reichert, U. Huber-Patz and H. Irngartinger, Liebigs Ann. Chem., 1993, 26, 403-411; D. P. Curran and S.-C. Kuo, J. Am. Chem. Soc., 1986, 108, 1106-1107; D. P. Curran and S.-C. Kuo, Tetrahedron, 1987, 43, 5653-5661; Y. K. Rao and M. Nagarajan, Tetrahedron Lett., 1988, 29, 107-108; Y. K. Rao and M. Nagarajan, J. Org. Chem., 1989, 54, 5678-5683. For modhephene see:; C.-K. Sha, T.-S. Jean, N.-T. Yau, S.-J. Huang, R.-T. Chiou, J.-F. Young, S.-H. Lih and W.-H. Tseng, J. Chinese Chem. Soc., 1995, 42, 637-640; C.-K. Sha, T.-S. Jean and D.-C. Wang, Tetrahedron Lett., 1990, 31, 3745-3748; C. P. Jasperse and D. P. Curran, J. Am. Chem. Soc., 1990, 112, 5601-5609; D. P. Curran and W. Shen, Tetrahedron, 1993, 49, 755-770; S. Kim, I. S. Kee and S. Lee, J. Am. Chem. Soc., 1991, 113, 9882-9883; H.-Y. Lee, D.-I. Kim and S. Kim, Bull. Korean Chem. Soc., 1999, 20, 269-270; H-Y. Lee, D.-I. Kim and S. Kim, Chem. Commun., 1996, 20, 1539-1540.
17. See for example: D. P. Curran and D. M. Rakiewicz, J. Am. Chem. Soc., 1985, 107, 1448-1449; D. P. Curran and D. M. Rakiewicz, Tetrahedron. 1985, 41, 3943-3958; D. P. Curran and M.-H. Chen, Tetrahedron Lett., 1985, 26, 4991-4994; K. Weinges, H. Reichert, U. Huber-Patz and H. Irngartinger, Liebigs Ann. Chem., 1993, 26, 403-411; D. P. Curran and S.-C. Kuo, J. Am. Chem. Soc., 1986, 108, 1106-1107; D. P. Curran and S.-C. Kuo, Tetrahedron, 1987, 43, 5653-5661; Y. K. Rao and M. Nagarajan, Tetrahedron Lett., 1988, 29, 107-108; Y. K. Rao and M. Nagarajan, J. Org. Chem., 1989, 54, 5678-5683. For modhephene see:; C.-K. Sha, T.-S. Jean, N.-T. Yau, S.-J. Huang, R.-T. Chiou, J.-F. Young, S.-H. Lih and W.-H. Tseng, J. Chinese Chem. Soc., 1995, 42, 637-640; C.-K. Sha, T.-S. Jean and D.-C. Wang, Tetrahedron Lett., 1990, 31, 3745-3748; C. P. Jasperse and D. P. Curran, J. Am. Chem. Soc., 1990, 112, 5601-5609; D. P. Curran and W. Shen, Tetrahedron, 1993, 49, 755-770; S. Kim, I. S. Kee and S. Lee, J. Am. Chem. Soc., 1991, 113, 9882-9883; H.-Y. Lee, D.-I. Kim and S. Kim, Bull. Korean Chem. Soc., 1999, 20, 269-270; H-Y. Lee, D.-I. Kim and S. Kim, Chem. Commun., 1996, 20, 1539-1540.
18. See for example: D. P. Curran and D. M. Rakiewicz, J. Am. Chem. Soc., 1985, 107, 1448-1449; D. P. Curran and D. M. Rakiewicz, Tetrahedron. 1985, 41, 3943-3958; D. P. Curran and M.-H. Chen, Tetrahedron Lett., 1985, 26, 4991-4994; K. Weinges, H. Reichert, U. Huber-Patz and H. Irngartinger, Liebigs Ann. Chem., 1993, 26, 403-411; D. P. Curran and S.-C. Kuo, J. Am. Chem. Soc., 1986, 108, 1106-1107; D. P. Curran and S.-C. Kuo, Tetrahedron, 1987, 43, 5653-5661; Y. K. Rao and M. Nagarajan, Tetrahedron Lett., 1988, 29, 107-108; Y. K. Rao and M. Nagarajan, J. Org. Chem., 1989, 54, 5678-5683. For modhephene see:; C.-K. Sha, T.-S. Jean, N.-T. Yau, S.-J. Huang, R.-T. Chiou, J.-F. Young, S.-H. Lih and W.-H. Tseng, J. Chinese Chem. Soc., 1995, 42, 637-640; C.-K. Sha, T.-S. Jean and D.-C. Wang, Tetrahedron Lett., 1990, 31, 3745-3748; C. P. Jasperse and D. P. Curran, J. Am. Chem. Soc., 1990, 112, 5601-5609; D. P. Curran and W. Shen, Tetrahedron, 1993, 49, 755-770; S. Kim, I. S. Kee and S. Lee, J. Am. Chem. Soc., 1991, 113, 9882-9883; H.-Y. Lee, D.-I. Kim and S. Kim, Bull. Korean Chem. Soc., 1999, 20, 269-270; H-Y. Lee, D.-I. Kim and S. Kim, Chem. Commun., 1996, 20, 1539-1540.
19. See for example: D. P. Curran and D. M. Rakiewicz, J. Am. Chem. Soc., 1985, 107, 1448-1449; D. P. Curran and D. M. Rakiewicz, Tetrahedron. 1985, 41, 3943-3958; D. P. Curran and M.-H. Chen, Tetrahedron Lett., 1985, 26, 4991-4994; K. Weinges, H. Reichert, U. Huber-Patz and H. Irngartinger, Liebigs Ann. Chem., 1993, 26, 403-411; D. P. Curran and S.-C. Kuo, J. Am. Chem. Soc., 1986, 108, 1106-1107; D. P. Curran and S.-C. Kuo, Tetrahedron, 1987, 43, 5653-5661; Y. K. Rao and M. Nagarajan, Tetrahedron Lett., 1988, 29, 107-108; Y. K. Rao and M. Nagarajan, J. Org. Chem., 1989, 54, 5678-5683. For modhephene see:; C.-K. Sha, T.-S. Jean, N.-T. Yau, S.-J. Huang, R.-T. Chiou, J.-F. Young, S.-H. Lih and W.-H. Tseng, J. Chinese Chem. Soc., 1995, 42, 637-640; C.-K. Sha, T.-S. Jean and D.-C. Wang, Tetrahedron Lett., 1990, 31, 3745-3748; C. P. Jasperse and D. P. Curran, J. Am. Chem. Soc., 1990, 112, 5601-5609; D. P. Curran and W. Shen, Tetrahedron, 1993, 49, 755-770; S. Kim, I. S. Kee and S. Lee, J. Am. Chem. Soc., 1991, 113, 9882-9883; H.-Y. Lee, D.-I. Kim and S. Kim, Bull. Korean Chem. Soc., 1999, 20, 269-270; H-Y. Lee, D.-I. Kim and S. Kim, Chem. Commun., 1996, 20, 1539-1540.
20. See for example: D. P. Curran and D. M. Rakiewicz, J. Am. Chem. Soc., 1985, 107, 1448-1449; D. P. Curran and D. M. Rakiewicz, Tetrahedron. 1985, 41, 3943-3958; D. P. Curran and M.-H. Chen, Tetrahedron Lett., 1985, 26, 4991-4994; K. Weinges, H. Reichert, U. Huber-Patz and H. Irngartinger, Liebigs Ann. Chem., 1993, 26, 403-411; D. P. Curran and S.-C. Kuo, J. Am. Chem. Soc., 1986, 108, 1106-1107; D. P. Curran and S.-C. Kuo, Tetrahedron, 1987, 43, 5653-5661; Y. K. Rao and M. Nagarajan, Tetrahedron Lett., 1988, 29, 107-108; Y. K. Rao and M. Nagarajan, J. Org. Chem., 1989, 54, 5678-5683. For modhephene see:; C.-K. Sha, T.-S. Jean, N.-T. Yau, S.-J. Huang, R.-T. Chiou, J.-F. Young, S.-H. Lih and W.-H. Tseng, J. Chinese Chem. Soc., 1995, 42, 637-640; C.-K. Sha, T.-S. Jean and D.-C. Wang, Tetrahedron Lett., 1990, 31, 3745-3748; C. P. Jasperse and D. P. Curran, J. Am. Chem. Soc., 1990, 112, 5601-5609; D. P. Curran and W. Shen, Tetrahedron, 1993, 49, 755-770; S. Kim, I. S. Kee and S. Lee, J. Am. Chem. Soc., 1991, 113, 9882-9883; H.-Y. Lee, D.-I. Kim and S. Kim, Bull. Korean Chem. Soc., 1999, 20, 269-270; H-Y. Lee, D.-I. Kim and S. Kim, Chem. Commun., 1996, 20, 1539-1540.
21. See for example: D. P. Curran and D. M. Rakiewicz, J. Am. Chem. Soc., 1985, 107, 1448-1449; D. P. Curran and D. M. Rakiewicz, Tetrahedron. 1985, 41, 3943-3958; D. P. Curran and M.-H. Chen, Tetrahedron Lett., 1985, 26, 4991-4994; K. Weinges, H. Reichert, U. Huber-Patz and H. Irngartinger, Liebigs Ann. Chem., 1993, 26, 403-411; D. P. Curran and S.-C. Kuo, J. Am. Chem. Soc., 1986, 108, 1106-1107; D. P. Curran and S.-C. Kuo, Tetrahedron, 1987, 43, 5653-5661; Y. K. Rao and M. Nagarajan, Tetrahedron Lett., 1988, 29, 107-108; Y. K. Rao and M. Nagarajan, J. Org. Chem., 1989, 54, 5678-5683. For modhephene see:; C.-K. Sha, T.-S. Jean, N.-T. Yau, S.-J. Huang, R.-T. Chiou, J.-F. Young, S.-H. Lih and W.-H. Tseng, J. Chinese Chem. Soc., 1995, 42, 637-640; C.-K. Sha, T.-S. Jean and D.-C. Wang, Tetrahedron Lett., 1990, 31, 3745-3748; C. P. Jasperse and D. P. Curran, J. Am. Chem. Soc., 1990, 112, 5601-5609; D. P. Curran and W. Shen, Tetrahedron, 1993, 49, 755-770; S. Kim, I. S. Kee and S. Lee, J. Am. Chem. Soc., 1991, 113, 9882-9883; H.-Y. Lee, D.-I. Kim and S. Kim, Bull. Korean Chem. Soc., 1999, 20, 269-270; H-Y. Lee, D.-I. Kim and S. Kim, Chem. Commun., 1996, 20, 1539-1540.
22. See for example: D. P. Curran and D. M. Rakiewicz, J. Am. Chem. Soc., 1985, 107, 1448-1449; D. P. Curran and D. M. Rakiewicz, Tetrahedron. 1985, 41, 3943-3958; D. P. Curran and M.-H. Chen, Tetrahedron Lett., 1985, 26, 4991-4994; K. Weinges, H. Reichert, U. Huber-Patz and H. Irngartinger, Liebigs Ann. Chem., 1993, 26, 403-411; D. P. Curran and S.-C. Kuo, J. Am. Chem. Soc., 1986, 108, 1106-1107; D. P. Curran and S.-C. Kuo, Tetrahedron, 1987, 43, 5653-5661; Y. K. Rao and M. Nagarajan, Tetrahedron Lett., 1988, 29, 107-108; Y. K. Rao and M. Nagarajan, J. Org. Chem., 1989, 54, 5678-5683. For modhephene see:; C.-K. Sha, T.-S. Jean, N.-T. Yau, S.-J. Huang, R.-T. Chiou, J.-F. Young, S.-H. Lih and W.-H. Tseng, J. Chinese Chem. Soc., 1995, 42, 637-640; C.-K. Sha, T.-S. Jean and D.-C. Wang, Tetrahedron Lett., 1990, 31, 3745-3748; C. P. Jasperse and D. P. Curran, J. Am. Chem. Soc., 1990, 112, 5601-5609; D. P. Curran and W. Shen, Tetrahedron, 1993, 49, 755-770; S. Kim, I. S. Kee and S. Lee, J. Am. Chem. Soc., 1991, 113, 9882-9883; H.-Y. Lee, D.-I. Kim and S. Kim, Bull. Korean Chem. Soc., 1999, 20, 269-270; H-Y. Lee, D.-I. Kim and S. Kim, Chem. Commun., 1996, 20, 1539-1540.
23. See for example: D. P. Curran and D. M. Rakiewicz, J. Am. Chem. Soc., 1985, 107, 1448-1449; D. P. Curran and D. M. Rakiewicz, Tetrahedron. 1985, 41, 3943-3958; D. P. Curran and M.-H. Chen, Tetrahedron Lett., 1985, 26, 4991-4994; K. Weinges, H. Reichert, U. Huber-Patz and H. Irngartinger, Liebigs Ann. Chem., 1993, 26, 403-411; D. P. Curran and S.-C. Kuo, J. Am. Chem. Soc., 1986, 108, 1106-1107; D. P. Curran and S.-C. Kuo, Tetrahedron, 1987, 43, 5653-5661; Y. K. Rao and M. Nagarajan, Tetrahedron Lett., 1988, 29, 107-108; Y. K. Rao and M. Nagarajan, J. Org. Chem., 1989, 54, 5678-5683. For modhephene see:; C.-K. Sha, T.-S. Jean, N.-T. Yau, S.-J. Huang, R.-T. Chiou, J.-F. Young, S.-H. Lih and W.-H. Tseng, J. Chinese Chem. Soc., 1995, 42, 637-640; C.-K. Sha, T.-S. Jean and D.-C. Wang, Tetrahedron Lett., 1990, 31, 3745-3748; C. P. Jasperse and D. P. Curran, J. Am. Chem. Soc., 1990, 112, 5601-5609; D. P. Curran and W. Shen, Tetrahedron, 1993, 49, 755-770; S. Kim, I. S. Kee and S. Lee, J. Am. Chem. Soc., 1991, 113, 9882-9883; H.-Y. Lee, D.-I. Kim and S. Kim, Bull. Korean Chem. Soc., 1999, 20, 269-270; H-Y. Lee, D.-I. Kim and S. Kim, Chem. Commun., 1996, 20, 1539-1540.
24. See for example: D. P. Curran and D. M. Rakiewicz, J. Am. Chem. Soc., 1985, 107, 1448-1449; D. P. Curran and D. M. Rakiewicz, Tetrahedron. 1985, 41, 3943-3958; D. P. Curran and M.-H. Chen, Tetrahedron Lett., 1985, 26, 4991-4994; K. Weinges, H. Reichert, U. Huber-Patz and H. Irngartinger, Liebigs Ann. Chem., 1993, 26, 403-411; D. P. Curran and S.-C. Kuo, J. Am. Chem. Soc., 1986, 108, 1106-1107; D. P. Curran and S.-C. Kuo, Tetrahedron, 1987, 43, 5653-5661; Y. K. Rao and M. Nagarajan, Tetrahedron Lett., 1988, 29, 107-108; Y. K. Rao and M. Nagarajan, J. Org. Chem., 1989, 54, 5678-5683. For modhephene see:; C.-K. Sha, T.-S. Jean, N.-T. Yau, S.-J. Huang, R.-T. Chiou, J.-F. Young, S.-H. Lih and W.-H. Tseng, J. Chinese Chem. Soc., 1995, 42, 637-640; C.-K. Sha, T.-S. Jean and D.-C. Wang, Tetrahedron Lett., 1990, 31, 3745-3748; C. P. Jasperse and D. P. Curran, J. Am. Chem. Soc., 1990, 112, 5601-5609; D. P. Curran and W. Shen, Tetrahedron, 1993, 49, 755-770; S. Kim, I. S. Kee and S. Lee, J. Am. Chem. Soc., 1991, 113, 9882-9883; H.-Y. Lee, D.-I. Kim and S. Kim, Bull. Korean Chem. Soc., 1999, 20, 269-270; H-Y. Lee, D.-I. Kim and S. Kim, Chem. Commun., 1996, 20, 1539-1540.
25. See: P. A. Wender, L. Sigget and J. M. Nuss, in Comprehensive Organic Synthesis, vol. 5, 645-673, Pergamon Press, Oxford, 1991.
26. See for example: G. Pattenden and S. J. Teague, Tetrahedron Lett., 1984, 25, 3021-3024; G. Pattenden and S. J. Teague, Tetrahedron, 1987, 43, 5637-5652; G. Mehta and K. S. Rao, J. Chem. Soc., Chem. Commun., 1985, 43, 1464-1465; G. Mehta and K. S. Rao, J. Am. Chem. Soc., 1986, 108, 8015-8021; S. Zhao, G. Mehta and P. Helquist, Tetrahedron Lett., 1991, 32, 5753-5756; G. L. Lange and C. Gottardo, J. Org. Chem., 1995, 60, 2183-2187.
27. See for example: G. Pattenden and S. J. Teague, Tetrahedron Lett., 1984, 25, 3021-3024; G. Pattenden and S. J. Teague, Tetrahedron, 1987, 43, 5637-5652; G. Mehta and K. S. Rao, J. Chem. Soc., Chem. Commun., 1985, 43, 1464-1465; G. Mehta and K. S. Rao, J. Am. Chem. Soc., 1986, 108, 8015-8021; S. Zhao, G. Mehta and P. Helquist, Tetrahedron Lett., 1991, 32, 5753-5756; G. L. Lange and C. Gottardo, J. Org. Chem., 1995, 60, 2183-2187.
28. See for example: G. Pattenden and S. J. Teague, Tetrahedron Lett., 1984, 25, 3021-3024; G. Pattenden and S. J. Teague, Tetrahedron, 1987, 43, 5637-5652; G. Mehta and K. S. Rao, J. Chem. Soc., Chem. Commun., 1985, 43, 1464-1465; G. Mehta and K. S. Rao, J. Am. Chem. Soc., 1986, 108, 8015-8021; S. Zhao, G. Mehta and P. Helquist, Tetrahedron Lett., 1991, 32, 5753-5756; G. L. Lange and C. Gottardo, J. Org. Chem., 1995, 60, 2183-2187.
29. See for example: G. Pattenden and S. J. Teague, Tetrahedron Lett., 1984, 25, 3021-3024; G. Pattenden and S. J. Teague, Tetrahedron, 1987, 43, 5637-5652; G. Mehta and K. S. Rao, J. Chem. Soc., Chem. Commun., 1985, 43, 1464-1465; G. Mehta and K. S. Rao, J. Am. Chem. Soc., 1986, 108, 8015-8021; S. Zhao, G. Mehta and P. Helquist, Tetrahedron Lett., 1991, 32, 5753-5756; G. L. Lange and C. Gottardo, J. Org. Chem., 1995, 60, 2183-2187.
30. See for example: G. Pattenden and S. J. Teague, Tetrahedron Lett., 1984, 25, 3021-3024; G. Pattenden and S. J. Teague, Tetrahedron, 1987, 43, 5637-5652; G. Mehta and K. S. Rao, J. Chem. Soc., Chem. Commun., 1985, 43, 1464-1465; G. Mehta and K. S. Rao, J. Am. Chem. Soc., 1986, 108, 8015-8021; S. Zhao, G. Mehta and P. Helquist, Tetrahedron Lett., 1991, 32, 5753-5756; G. L. Lange and C. Gottardo, J. Org. Chem., 1995, 60, 2183-2187.
31. See for example: G. Pattenden and S. J. Teague, Tetrahedron Lett., 1984, 25, 3021-3024; G. Pattenden and S. J. Teague, Tetrahedron, 1987, 43, 5637-5652; G. Mehta and K. S. Rao, J. Chem. Soc., Chem. Commun., 1985, 43, 1464-1465; G. Mehta and K. S. Rao, J. Am. Chem. Soc., 1986, 108, 8015-8021; S. Zhao, G. Mehta and P. Helquist, Tetrahedron Lett., 1991, 32, 5753-5756; G. L. Lange and C. Gottardo, J. Org. Chem., 1995, 60, 2183-2187.
32. (a) C. J. Hayes, N. M. A. Herbert, N. M. Harrington-Frost and G. Pattenden, Org. Biomol. Chem., 2004, DOI: 10.1039/b413815p;
33. (b) B. De Boeck, N. M. A. Herbert, N. M. Harrington-Frost and G. Pattenden, Org. Biomol. Chem., 2004, DOI: 10.1039/b13816n.
34. For earlier syntheses of pentalenene, see: G. D. Annis and L. A. Paquette. J. Am. Chem. Soc., 1982, 104, 4504-4506; L. A. Raquette and G. D. Annis, J. Am. Chem. Soc., 1983, 105, 7358-7363; E. Piers and V. Karunaratne, J. Chem. Soc., Chem. Commun., 1984, 105. 959-960; E. Piers and V. Karunaratne, Can. J. Chem., 1989, 105, 160-164; D. H. Hua, J. Am. Chem. Soc., 1986, 108, 3835-3837; T. Imanishi, F. Ninbari, M. Yamashita and C. Iwata, Chem. Pharm. Bull, 1986, 34, 2268-2271: T. Imanishi, M. Yamashita, F. Ninbari, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1988, 36, 1371-1378; T. Imanishi, M. Yamashita, Y. Hirokawa, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1990, 38, 1124-1128; T. Hudlicky, M. G. Natchus and G. Sinai-Zingde, J. Org. Chem., 1987, 52, 4641-4644; T. Hudlicky, G. Sinai-Zingde, M. G. Natchus, B. C. Ranu and P. Papadopolous, Tetrahedron, 1987, 43, 5685-5721; Y. Shizuri, S. Maki, M. Ohkubo and S. Yamamura, Tetrahedron Lett., 1990, 31, 7167-7168; M. Franck-Neumann, M. Miesch and L. Gross, Tetrahedron Lett., 1992, 33, 3879-3882: M. Miesch, L. Miesch-Gross and M. Franck-Neumann, Tetrahedron, 1997, 53, 2111-2118; M. Hatanaka, F. Uena and I. Ueda, Tetrahedron Lett., 1996, 37, 89-90; M. T. Crimmins and J. A. DeLoach, J. Am. Chem Soc., 1986, 108, 800-804; Y-J. Wu and D. J. Burnell, J. Chem. Soc., Chem. Commun., 1991, 108, 764-765; Y.-J. Wu, Y.-Y. Zhu and D. J. Burnell, J. Org. Chem., 1994, 59, 104-110; see ref. 4 . For syntheses of modhephene, see:; M. Karpf and A. S. Dreiding, Tetrahedron Lett., 1980, 21, 4569-4570; A. B. Smith III and P. J. Jerris, J. Am. Chem. Soc, 1981, 103. 194-195; L. A. Paquette and H. Schostarez, J. Am. Chem. Soc., 1981, 103, 722-724; W. Oppolzer and F. Marazza, Helv. Chim. Acta. 1981, 64, 1575-1578; W. Oppolzer and K. Baettig, Hely. Chim. Acta, 1981, 64, 2489-2491; J. Wrobel, K. Takahashi, V. Honkan, G. Lannoye, J. M. Cook and S. H. Bertz, J. Org. Chem., 1983, 48, 139-141; E. A. Mash, S. K. Math and C. J. Flann, Tetrahedron Lett., 1988, 29, 2147-2150; and also under ref. 3 in this paper.
35. For earlier syntheses of pentalenene, see: G. D. Annis and L. A. Paquette. J. Am. Chem. Soc., 1982, 104, 4504-4506; L. A. Raquette and G. D. Annis, J. Am. Chem. Soc., 1983, 105, 7358-7363; E. Piers and V. Karunaratne, J. Chem. Soc., Chem. Commun., 1984, 105. 959-960; E. Piers and V. Karunaratne, Can. J. Chem., 1989, 105, 160-164; D. H. Hua, J. Am. Chem. Soc., 1986, 108, 3835-3837; T. Imanishi, F. Ninbari, M. Yamashita and C. Iwata, Chem. Pharm. Bull, 1986, 34, 2268-2271: T. Imanishi, M. Yamashita, F. Ninbari, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1988, 36, 1371-1378; T. Imanishi, M. Yamashita, Y. Hirokawa, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1990, 38, 1124-1128; T. Hudlicky, M. G. Natchus and G. Sinai-Zingde, J. Org. Chem., 1987, 52, 4641-4644; T. Hudlicky, G. Sinai-Zingde, M. G. Natchus, B. C. Ranu and P. Papadopolous, Tetrahedron, 1987, 43, 5685-5721; Y. Shizuri, S. Maki, M. Ohkubo and S. Yamamura, Tetrahedron Lett., 1990, 31, 7167-7168; M. Franck-Neumann, M. Miesch and L. Gross, Tetrahedron Lett., 1992, 33, 3879-3882: M. Miesch, L. Miesch-Gross and M. Franck-Neumann, Tetrahedron, 1997, 53, 2111-2118; M. Hatanaka, F. Uena and I. Ueda, Tetrahedron Lett., 1996, 37, 89-90; M. T. Crimmins and J. A. DeLoach, J. Am. Chem Soc., 1986, 108, 800-804; Y-J. Wu and D. J. Burnell, J. Chem. Soc., Chem. Commun., 1991, 108, 764-765; Y.-J. Wu, Y.-Y. Zhu and D. J. Burnell, J. Org. Chem., 1994, 59, 104-110; see ref. 4 . For syntheses of modhephene, see:; M. Karpf and A. S. Dreiding, Tetrahedron Lett., 1980, 21, 4569-4570; A. B. Smith III and P. J. Jerris, J. Am. Chem. Soc, 1981, 103. 194-195; L. A. Paquette and H. Schostarez, J. Am. Chem. Soc., 1981, 103, 722-724; W. Oppolzer and F. Marazza, Helv. Chim. Acta. 1981, 64, 1575-1578; W. Oppolzer and K. Baettig, Hely. Chim. Acta, 1981, 64, 2489-2491; J. Wrobel, K. Takahashi, V. Honkan, G. Lannoye, J. M. Cook and S. H. Bertz, J. Org. Chem., 1983, 48, 139-141; E. A. Mash, S. K. Math and C. J. Flann, Tetrahedron Lett., 1988, 29, 2147-2150; and also under ref. 3 in this paper.
36. For earlier syntheses of pentalenene, see: G. D. Annis and L. A. Paquette. J. Am. Chem. Soc., 1982, 104, 4504-4506; L. A. Raquette and G. D. Annis, J. Am. Chem. Soc., 1983, 105, 7358-7363; E. Piers and V. Karunaratne, J. Chem. Soc., Chem. Commun., 1984, 105. 959-960; E. Piers and V. Karunaratne, Can. J. Chem., 1989, 105, 160-164; D. H. Hua, J. Am. Chem. Soc., 1986, 108, 3835-3837; T. Imanishi, F. Ninbari, M. Yamashita and C. Iwata, Chem. Pharm. Bull, 1986, 34, 2268-2271: T. Imanishi, M. Yamashita, F. Ninbari, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1988, 36, 1371-1378; T. Imanishi, M. Yamashita, Y. Hirokawa, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1990, 38, 1124-1128; T. Hudlicky, M. G. Natchus and G. Sinai-Zingde, J. Org. Chem., 1987, 52, 4641-4644; T. Hudlicky, G. Sinai-Zingde, M. G. Natchus, B. C. Ranu and P. Papadopolous, Tetrahedron, 1987, 43, 5685-5721; Y. Shizuri, S. Maki, M. Ohkubo and S. Yamamura, Tetrahedron Lett., 1990, 31, 7167-7168; M. Franck-Neumann, M. Miesch and L. Gross, Tetrahedron Lett., 1992, 33, 3879-3882: M. Miesch, L. Miesch-Gross and M. Franck-Neumann, Tetrahedron, 1997, 53, 2111-2118; M. Hatanaka, F. Uena and I. Ueda, Tetrahedron Lett., 1996, 37, 89-90; M. T. Crimmins and J. A. DeLoach, J. Am. Chem Soc., 1986, 108, 800-804; Y-J. Wu and D. J. Burnell, J. Chem. Soc., Chem. Commun., 1991, 108, 764-765; Y.-J. Wu, Y.-Y. Zhu and D. J. Burnell, J. Org. Chem., 1994, 59, 104-110; see ref. 4 . For syntheses of modhephene, see:; M. Karpf and A. S. Dreiding, Tetrahedron Lett., 1980, 21, 4569-4570; A. B. Smith III and P. J. Jerris, J. Am. Chem. Soc, 1981, 103. 194-195; L. A. Paquette and H. Schostarez, J. Am. Chem. Soc., 1981, 103, 722-724; W. Oppolzer and F. Marazza, Helv. Chim. Acta. 1981, 64, 1575-1578; W. Oppolzer and K. Baettig, Hely. Chim. Acta, 1981, 64, 2489-2491; J. Wrobel, K. Takahashi, V. Honkan, G. Lannoye, J. M. Cook and S. H. Bertz, J. Org. Chem., 1983, 48, 139-141; E. A. Mash, S. K. Math and C. J. Flann, Tetrahedron Lett., 1988, 29, 2147-2150; and also under ref. 3 in this paper.
37. For earlier syntheses of pentalenene, see: G. D. Annis and L. A. Paquette. J. Am. Chem. Soc., 1982, 104, 4504-4506; L. A. Raquette and G. D. Annis, J. Am. Chem. Soc., 1983, 105, 7358-7363; E. Piers and V. Karunaratne, J. Chem. Soc., Chem. Commun., 1984, 105. 959-960; E. Piers and V. Karunaratne, Can. J. Chem., 1989, 105, 160-164; D. H. Hua, J. Am. Chem. Soc., 1986, 108, 3835-3837; T. Imanishi, F. Ninbari, M. Yamashita and C. Iwata, Chem. Pharm. Bull, 1986, 34, 2268-2271: T. Imanishi, M. Yamashita, F. Ninbari, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1988, 36, 1371-1378; T. Imanishi, M. Yamashita, Y. Hirokawa, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1990, 38, 1124-1128; T. Hudlicky, M. G. Natchus and G. Sinai-Zingde, J. Org. Chem., 1987, 52, 4641-4644; T. Hudlicky, G. Sinai-Zingde, M. G. Natchus, B. C. Ranu and P. Papadopolous, Tetrahedron, 1987, 43, 5685-5721; Y. Shizuri, S. Maki, M. Ohkubo and S. Yamamura, Tetrahedron Lett., 1990, 31, 7167-7168; M. Franck-Neumann, M. Miesch and L. Gross, Tetrahedron Lett., 1992, 33, 3879-3882: M. Miesch, L. Miesch-Gross and M. Franck-Neumann, Tetrahedron, 1997, 53, 2111-2118; M. Hatanaka, F. Uena and I. Ueda, Tetrahedron Lett., 1996, 37, 89-90; M. T. Crimmins and J. A. DeLoach, J. Am. Chem Soc., 1986, 108, 800-804; Y-J. Wu and D. J. Burnell, J. Chem. Soc., Chem. Commun., 1991, 108, 764-765; Y.-J. Wu, Y.-Y. Zhu and D. J. Burnell, J. Org. Chem., 1994, 59, 104-110; see ref. 4 . For syntheses of modhephene, see:; M. Karpf and A. S. Dreiding, Tetrahedron Lett., 1980, 21, 4569-4570; A. B. Smith III and P. J. Jerris, J. Am. Chem. Soc, 1981, 103. 194-195; L. A. Paquette and H. Schostarez, J. Am. Chem. Soc., 1981, 103, 722-724; W. Oppolzer and F. Marazza, Helv. Chim. Acta. 1981, 64, 1575-1578; W. Oppolzer and K. Baettig, Hely. Chim. Acta, 1981, 64, 2489-2491; J. Wrobel, K. Takahashi, V. Honkan, G. Lannoye, J. M. Cook and S. H. Bertz, J. Org. Chem., 1983, 48, 139-141; E. A. Mash, S. K. Math and C. J. Flann, Tetrahedron Lett., 1988, 29, 2147-2150; and also under ref. 3 in this paper.
38. For earlier syntheses of pentalenene, see: G. D. Annis and L. A. Paquette. J. Am. Chem. Soc., 1982, 104, 4504-4506; L. A. Raquette and G. D. Annis, J. Am. Chem. Soc., 1983, 105, 7358-7363; E. Piers and V. Karunaratne, J. Chem. Soc., Chem. Commun., 1984, 105. 959-960; E. Piers and V. Karunaratne, Can. J. Chem., 1989, 105, 160-164; D. H. Hua, J. Am. Chem. Soc., 1986, 108, 3835-3837; T. Imanishi, F. Ninbari, M. Yamashita and C. Iwata, Chem. Pharm. Bull, 1986, 34, 2268-2271: T. Imanishi, M. Yamashita, F. Ninbari, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1988, 36, 1371-1378; T. Imanishi, M. Yamashita, Y. Hirokawa, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1990, 38, 1124-1128; T. Hudlicky, M. G. Natchus and G. Sinai-Zingde, J. Org. Chem., 1987, 52, 4641-4644; T. Hudlicky, G. Sinai-Zingde, M. G. Natchus, B. C. Ranu and P. Papadopolous, Tetrahedron, 1987, 43, 5685-5721; Y. Shizuri, S. Maki, M. Ohkubo and S. Yamamura, Tetrahedron Lett., 1990, 31, 7167-7168; M. Franck-Neumann, M. Miesch and L. Gross, Tetrahedron Lett., 1992, 33, 3879-3882: M. Miesch, L. Miesch-Gross and M. Franck-Neumann, Tetrahedron, 1997, 53, 2111-2118; M. Hatanaka, F. Uena and I. Ueda, Tetrahedron Lett., 1996, 37, 89-90; M. T. Crimmins and J. A. DeLoach, J. Am. Chem Soc., 1986, 108, 800-804; Y-J. Wu and D. J. Burnell, J. Chem. Soc., Chem. Commun., 1991, 108, 764-765; Y.-J. Wu, Y.-Y. Zhu and D. J. Burnell, J. Org. Chem., 1994, 59, 104-110; see ref. 4 . For syntheses of modhephene, see:; M. Karpf and A. S. Dreiding, Tetrahedron Lett., 1980, 21, 4569-4570; A. B. Smith III and P. J. Jerris, J. Am. Chem. Soc, 1981, 103. 194-195; L. A. Paquette and H. Schostarez, J. Am. Chem. Soc., 1981, 103, 722-724; W. Oppolzer and F. Marazza, Helv. Chim. Acta. 1981, 64, 1575-1578; W. Oppolzer and K. Baettig, Hely. Chim. Acta, 1981, 64, 2489-2491; J. Wrobel, K. Takahashi, V. Honkan, G. Lannoye, J. M. Cook and S. H. Bertz, J. Org. Chem., 1983, 48, 139-141; E. A. Mash, S. K. Math and C. J. Flann, Tetrahedron Lett., 1988, 29, 2147-2150; and also under ref. 3 in this paper.
39. For earlier syntheses of pentalenene, see: G. D. Annis and L. A. Paquette. J. Am. Chem. Soc., 1982, 104, 4504-4506; L. A. Raquette and G. D. Annis, J. Am. Chem. Soc., 1983, 105, 7358-7363; E. Piers and V. Karunaratne, J. Chem. Soc., Chem. Commun., 1984, 105. 959-960; E. Piers and V. Karunaratne, Can. J. Chem., 1989, 105, 160-164; D. H. Hua, J. Am. Chem. Soc., 1986, 108, 3835-3837; T. Imanishi, F. Ninbari, M. Yamashita and C. Iwata, Chem. Pharm. Bull, 1986, 34, 2268-2271: T. Imanishi, M. Yamashita, F. Ninbari, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1988, 36, 1371-1378; T. Imanishi, M. Yamashita, Y. Hirokawa, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1990, 38, 1124-1128; T. Hudlicky, M. G. Natchus and G. Sinai-Zingde, J. Org. Chem., 1987, 52, 4641-4644; T. Hudlicky, G. Sinai-Zingde, M. G. Natchus, B. C. Ranu and P. Papadopolous, Tetrahedron, 1987, 43, 5685-5721; Y. Shizuri, S. Maki, M. Ohkubo and S. Yamamura, Tetrahedron Lett., 1990, 31, 7167-7168; M. Franck-Neumann, M. Miesch and L. Gross, Tetrahedron Lett., 1992, 33, 3879-3882: M. Miesch, L. Miesch-Gross and M. Franck-Neumann, Tetrahedron, 1997, 53, 2111-2118; M. Hatanaka, F. Uena and I. Ueda, Tetrahedron Lett., 1996, 37, 89-90; M. T. Crimmins and J. A. DeLoach, J. Am. Chem Soc., 1986, 108, 800-804; Y-J. Wu and D. J. Burnell, J. Chem. Soc., Chem. Commun., 1991, 108, 764-765; Y.-J. Wu, Y.-Y. Zhu and D. J. Burnell, J. Org. Chem., 1994, 59, 104-110; see ref. 4 . For syntheses of modhephene, see:; M. Karpf and A. S. Dreiding, Tetrahedron Lett., 1980, 21, 4569-4570; A. B. Smith III and P. J. Jerris, J. Am. Chem. Soc, 1981, 103. 194-195; L. A. Paquette and H. Schostarez, J. Am. Chem. Soc., 1981, 103, 722-724; W. Oppolzer and F. Marazza, Helv. Chim. Acta. 1981, 64, 1575-1578; W. Oppolzer and K. Baettig, Hely. Chim. Acta, 1981, 64, 2489-2491; J. Wrobel, K. Takahashi, V. Honkan, G. Lannoye, J. M. Cook and S. H. Bertz, J. Org. Chem., 1983, 48, 139-141; E. A. Mash, S. K. Math and C. J. Flann, Tetrahedron Lett., 1988, 29, 2147-2150; and also under ref. 3 in this paper.
40. For earlier syntheses of pentalenene, see: G. D. Annis and L. A. Paquette. J. Am. Chem. Soc., 1982, 104, 4504-4506; L. A. Raquette and G. D. Annis, J. Am. Chem. Soc., 1983, 105, 7358-7363; E. Piers and V. Karunaratne, J. Chem. Soc., Chem. Commun., 1984, 105. 959-960; E. Piers and V. Karunaratne, Can. J. Chem., 1989, 105, 160-164; D. H. Hua, J. Am. Chem. Soc., 1986, 108, 3835-3837; T. Imanishi, F. Ninbari, M. Yamashita and C. Iwata, Chem. Pharm. Bull, 1986, 34, 2268-2271: T. Imanishi, M. Yamashita, F. Ninbari, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1988, 36, 1371-1378; T. Imanishi, M. Yamashita, Y. Hirokawa, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1990, 38, 1124-1128; T. Hudlicky, M. G. Natchus and G. Sinai-Zingde, J. Org. Chem., 1987, 52, 4641-4644; T. Hudlicky, G. Sinai-Zingde, M. G. Natchus, B. C. Ranu and P. Papadopolous, Tetrahedron, 1987, 43, 5685-5721; Y. Shizuri, S. Maki, M. Ohkubo and S. Yamamura, Tetrahedron Lett., 1990, 31, 7167-7168; M. Franck-Neumann, M. Miesch and L. Gross, Tetrahedron Lett., 1992, 33, 3879-3882: M. Miesch, L. Miesch-Gross and M. Franck-Neumann, Tetrahedron, 1997, 53, 2111-2118; M. Hatanaka, F. Uena and I. Ueda, Tetrahedron Lett., 1996, 37, 89-90; M. T. Crimmins and J. A. DeLoach, J. Am. Chem Soc., 1986, 108, 800-804; Y-J. Wu and D. J. Burnell, J. Chem. Soc., Chem. Commun., 1991, 108, 764-765; Y.-J. Wu, Y.-Y. Zhu and D. J. Burnell, J. Org. Chem., 1994, 59, 104-110; see ref. 4 . For syntheses of modhephene, see:; M. Karpf and A. S. Dreiding, Tetrahedron Lett., 1980, 21, 4569-4570; A. B. Smith III and P. J. Jerris, J. Am. Chem. Soc, 1981, 103. 194-195; L. A. Paquette and H. Schostarez, J. Am. Chem. Soc., 1981, 103, 722-724; W. Oppolzer and F. Marazza, Helv. Chim. Acta. 1981, 64, 1575-1578; W. Oppolzer and K. Baettig, Hely. Chim. Acta, 1981, 64, 2489-2491; J. Wrobel, K. Takahashi, V. Honkan, G. Lannoye, J. M. Cook and S. H. Bertz, J. Org. Chem., 1983, 48, 139-141; E. A. Mash, S. K. Math and C. J. Flann, Tetrahedron Lett., 1988, 29, 2147-2150; and also under ref. 3 in this paper.
41. For earlier syntheses of pentalenene, see: G. D. Annis and L. A. Paquette. J. Am. Chem. Soc., 1982, 104, 4504-4506; L. A. Raquette and G. D. Annis, J. Am. Chem. Soc., 1983, 105, 7358-7363; E. Piers and V. Karunaratne, J. Chem. Soc., Chem. Commun., 1984, 105. 959-960; E. Piers and V. Karunaratne, Can. J. Chem., 1989, 105, 160-164; D. H. Hua, J. Am. Chem. Soc., 1986, 108, 3835-3837; T. Imanishi, F. Ninbari, M. Yamashita and C. Iwata, Chem. Pharm. Bull, 1986, 34, 2268-2271: T. Imanishi, M. Yamashita, F. Ninbari, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1988, 36, 1371-1378; T. Imanishi, M. Yamashita, Y. Hirokawa, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1990, 38, 1124-1128; T. Hudlicky, M. G. Natchus and G. Sinai-Zingde, J. Org. Chem., 1987, 52, 4641-4644; T. Hudlicky, G. Sinai-Zingde, M. G. Natchus, B. C. Ranu and P. Papadopolous, Tetrahedron, 1987, 43, 5685-5721; Y. Shizuri, S. Maki, M. Ohkubo and S. Yamamura, Tetrahedron Lett., 1990, 31, 7167-7168; M. Franck-Neumann, M. Miesch and L. Gross, Tetrahedron Lett., 1992, 33, 3879-3882: M. Miesch, L. Miesch-Gross and M. Franck-Neumann, Tetrahedron, 1997, 53, 2111-2118; M. Hatanaka, F. Uena and I. Ueda, Tetrahedron Lett., 1996, 37, 89-90; M. T. Crimmins and J. A. DeLoach, J. Am. Chem Soc., 1986, 108, 800-804; Y-J. Wu and D. J. Burnell, J. Chem. Soc., Chem. Commun., 1991, 108, 764-765; Y.-J. Wu, Y.-Y. Zhu and D. J. Burnell, J. Org. Chem., 1994, 59, 104-110; see ref. 4 . For syntheses of modhephene, see:; M. Karpf and A. S. Dreiding, Tetrahedron Lett., 1980, 21, 4569-4570; A. B. Smith III and P. J. Jerris, J. Am. Chem. Soc, 1981, 103. 194-195; L. A. Paquette and H. Schostarez, J. Am. Chem. Soc., 1981, 103, 722-724; W. Oppolzer and F. Marazza, Helv. Chim. Acta. 1981, 64, 1575-1578; W. Oppolzer and K. Baettig, Hely. Chim. Acta, 1981, 64, 2489-2491; J. Wrobel, K. Takahashi, V. Honkan, G. Lannoye, J. M. Cook and S. H. Bertz, J. Org. Chem., 1983, 48, 139-141; E. A. Mash, S. K. Math and C. J. Flann, Tetrahedron Lett., 1988, 29, 2147-2150; and also under ref. 3 in this paper.
42. For earlier syntheses of pentalenene, see: G. D. Annis and L. A. Paquette. J. Am. Chem. Soc., 1982, 104, 4504-4506; L. A. Raquette and G. D. Annis, J. Am. Chem. Soc., 1983, 105, 7358-7363; E. Piers and V. Karunaratne, J. Chem. Soc., Chem. Commun., 1984, 105. 959-960; E. Piers and V. Karunaratne, Can. J. Chem., 1989, 105, 160-164; D. H. Hua, J. Am. Chem. Soc., 1986, 108, 3835-3837; T. Imanishi, F. Ninbari, M. Yamashita and C. Iwata, Chem. Pharm. Bull, 1986, 34, 2268-2271: T. Imanishi, M. Yamashita, F. Ninbari, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1988, 36, 1371-1378; T. Imanishi, M. Yamashita, Y. Hirokawa, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1990, 38, 1124-1128; T. Hudlicky, M. G. Natchus and G. Sinai-Zingde, J. Org. Chem., 1987, 52, 4641-4644; T. Hudlicky, G. Sinai-Zingde, M. G. Natchus, B. C. Ranu and P. Papadopolous, Tetrahedron, 1987, 43, 5685-5721; Y. Shizuri, S. Maki, M. Ohkubo and S. Yamamura, Tetrahedron Lett., 1990, 31, 7167-7168; M. Franck-Neumann, M. Miesch and L. Gross, Tetrahedron Lett., 1992, 33, 3879-3882: M. Miesch, L. Miesch-Gross and M. Franck-Neumann, Tetrahedron, 1997, 53, 2111-2118; M. Hatanaka, F. Uena and I. Ueda, Tetrahedron Lett., 1996, 37, 89-90; M. T. Crimmins and J. A. DeLoach, J. Am. Chem Soc., 1986, 108, 800-804; Y-J. Wu and D. J. Burnell, J. Chem. Soc., Chem. Commun., 1991, 108, 764-765; Y.-J. Wu, Y.-Y. Zhu and D. J. Burnell, J. Org. Chem., 1994, 59, 104-110; see ref. 4 . For syntheses of modhephene, see:; M. Karpf and A. S. Dreiding, Tetrahedron Lett., 1980, 21, 4569-4570; A. B. Smith III and P. J. Jerris, J. Am. Chem. Soc, 1981, 103. 194-195; L. A. Paquette and H. Schostarez, J. Am. Chem. Soc., 1981, 103, 722-724; W. Oppolzer and F. Marazza, Helv. Chim. Acta. 1981, 64, 1575-1578; W. Oppolzer and K. Baettig, Hely. Chim. Acta, 1981, 64, 2489-2491; J. Wrobel, K. Takahashi, V. Honkan, G. Lannoye, J. M. Cook and S. H. Bertz, J. Org. Chem., 1983, 48, 139-141; E. A. Mash, S. K. Math and C. J. Flann, Tetrahedron Lett., 1988, 29, 2147-2150; and also under ref. 3 in this paper.
43. For earlier syntheses of pentalenene, see: G. D. Annis and L. A. Paquette. J. Am. Chem. Soc., 1982, 104, 4504-4506; L. A. Raquette and G. D. Annis, J. Am. Chem. Soc., 1983, 105, 7358-7363; E. Piers and V. Karunaratne, J. Chem. Soc., Chem. Commun., 1984, 105. 959-960; E. Piers and V. Karunaratne, Can. J. Chem., 1989, 105, 160-164; D. H. Hua, J. Am. Chem. Soc., 1986, 108, 3835-3837; T. Imanishi, F. Ninbari, M. Yamashita and C. Iwata, Chem. Pharm. Bull, 1986, 34, 2268-2271: T. Imanishi, M. Yamashita, F. Ninbari, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1988, 36, 1371-1378; T. Imanishi, M. Yamashita, Y. Hirokawa, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1990, 38, 1124-1128; T. Hudlicky, M. G. Natchus and G. Sinai-Zingde, J. Org. Chem., 1987, 52, 4641-4644; T. Hudlicky, G. Sinai-Zingde, M. G. Natchus, B. C. Ranu and P. Papadopolous, Tetrahedron, 1987, 43, 5685-5721; Y. Shizuri, S. Maki, M. Ohkubo and S. Yamamura, Tetrahedron Lett., 1990, 31, 7167-7168; M. Franck-Neumann, M. Miesch and L. Gross, Tetrahedron Lett., 1992, 33, 3879-3882: M. Miesch, L. Miesch-Gross and M. Franck-Neumann, Tetrahedron, 1997, 53, 2111-2118; M. Hatanaka, F. Uena and I. Ueda, Tetrahedron Lett., 1996, 37, 89-90; M. T. Crimmins and J. A. DeLoach, J. Am. Chem Soc., 1986, 108, 800-804; Y-J. Wu and D. J. Burnell, J. Chem. Soc., Chem. Commun., 1991, 108, 764-765; Y.-J. Wu, Y.-Y. Zhu and D. J. Burnell, J. Org. Chem., 1994, 59, 104-110; see ref. 4 . For syntheses of modhephene, see:; M. Karpf and A. S. Dreiding, Tetrahedron Lett., 1980, 21, 4569-4570; A. B. Smith III and P. J. Jerris, J. Am. Chem. Soc, 1981, 103. 194-195; L. A. Paquette and H. Schostarez, J. Am. Chem. Soc., 1981, 103, 722-724; W. Oppolzer and F. Marazza, Helv. Chim. Acta. 1981, 64, 1575-1578; W. Oppolzer and K. Baettig, Hely. Chim. Acta, 1981, 64, 2489-2491; J. Wrobel, K. Takahashi, V. Honkan, G. Lannoye, J. M. Cook and S. H. Bertz, J. Org. Chem., 1983, 48, 139-141; E. A. Mash, S. K. Math and C. J. Flann, Tetrahedron Lett., 1988, 29, 2147-2150; and also under ref. 3 in this paper.
44. For earlier syntheses of pentalenene, see: G. D. Annis and L. A. Paquette. J. Am. Chem. Soc., 1982, 104, 4504-4506; L. A. Raquette and G. D. Annis, J. Am. Chem. Soc., 1983, 105, 7358-7363; E. Piers and V. Karunaratne, J. Chem. Soc., Chem. Commun., 1984, 105. 959-960; E. Piers and V. Karunaratne, Can. J. Chem., 1989, 105, 160-164; D. H. Hua, J. Am. Chem. Soc., 1986, 108, 3835-3837; T. Imanishi, F. Ninbari, M. Yamashita and C. Iwata, Chem. Pharm. Bull, 1986, 34, 2268-2271: T. Imanishi, M. Yamashita, F. Ninbari, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1988, 36, 1371-1378; T. Imanishi, M. Yamashita, Y. Hirokawa, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1990, 38, 1124-1128; T. Hudlicky, M. G. Natchus and G. Sinai-Zingde, J. Org. Chem., 1987, 52, 4641-4644; T. Hudlicky, G. Sinai-Zingde, M. G. Natchus, B. C. Ranu and P. Papadopolous, Tetrahedron, 1987, 43, 5685-5721; Y. Shizuri, S. Maki, M. Ohkubo and S. Yamamura, Tetrahedron Lett., 1990, 31, 7167-7168; M. Franck-Neumann, M. Miesch and L. Gross, Tetrahedron Lett., 1992, 33, 3879-3882: M. Miesch, L. Miesch-Gross and M. Franck-Neumann, Tetrahedron, 1997, 53, 2111-2118; M. Hatanaka, F. Uena and I. Ueda, Tetrahedron Lett., 1996, 37, 89-90; M. T. Crimmins and J. A. DeLoach, J. Am. Chem Soc., 1986, 108, 800-804; Y-J. Wu and D. J. Burnell, J. Chem. Soc., Chem. Commun., 1991, 108, 764-765; Y.-J. Wu, Y.-Y. Zhu and D. J. Burnell, J. Org. Chem., 1994, 59, 104-110; see ref. 4 . For syntheses of modhephene, see:; M. Karpf and A. S. Dreiding, Tetrahedron Lett., 1980, 21, 4569-4570; A. B. Smith III and P. J. Jerris, J. Am. Chem. Soc, 1981, 103. 194-195; L. A. Paquette and H. Schostarez, J. Am. Chem. Soc., 1981, 103, 722-724; W. Oppolzer and F. Marazza, Helv. Chim. Acta. 1981, 64, 1575-1578; W. Oppolzer and K. Baettig, Hely. Chim. Acta, 1981, 64, 2489-2491; J. Wrobel, K. Takahashi, V. Honkan, G. Lannoye, J. M. Cook and S. H. Bertz, J. Org. Chem., 1983, 48, 139-141; E. A. Mash, S. K. Math and C. J. Flann, Tetrahedron Lett., 1988, 29, 2147-2150; and also under ref. 3 in this paper.
45. For earlier syntheses of pentalenene, see: G. D. Annis and L. A. Paquette. J. Am. Chem. Soc., 1982, 104, 4504-4506; L. A. Raquette and G. D. Annis, J. Am. Chem. Soc., 1983, 105, 7358-7363; E. Piers and V. Karunaratne, J. Chem. Soc., Chem. Commun., 1984, 105. 959-960; E. Piers and V. Karunaratne, Can. J. Chem., 1989, 105, 160-164; D. H. Hua, J. Am. Chem. Soc., 1986, 108, 3835-3837; T. Imanishi, F. Ninbari, M. Yamashita and C. Iwata, Chem. Pharm. Bull, 1986, 34, 2268-2271: T. Imanishi, M. Yamashita, F. Ninbari, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1988, 36, 1371-1378; T. Imanishi, M. Yamashita, Y. Hirokawa, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1990, 38, 1124-1128; T. Hudlicky, M. G. Natchus and G. Sinai-Zingde, J. Org. Chem., 1987, 52, 4641-4644; T. Hudlicky, G. Sinai-Zingde, M. G. Natchus, B. C. Ranu and P. Papadopolous, Tetrahedron, 1987, 43, 5685-5721; Y. Shizuri, S. Maki, M. Ohkubo and S. Yamamura, Tetrahedron Lett., 1990, 31, 7167-7168; M. Franck-Neumann, M. Miesch and L. Gross, Tetrahedron Lett., 1992, 33, 3879-3882: M. Miesch, L. Miesch-Gross and M. Franck-Neumann, Tetrahedron, 1997, 53, 2111-2118; M. Hatanaka, F. Uena and I. Ueda, Tetrahedron Lett., 1996, 37, 89-90; M. T. Crimmins and J. A. DeLoach, J. Am. Chem Soc., 1986, 108, 800-804; Y-J. Wu and D. J. Burnell, J. Chem. Soc., Chem. Commun., 1991, 108, 764-765; Y.-J. Wu, Y.-Y. Zhu and D. J. Burnell, J. Org. Chem., 1994, 59, 104-110; see ref. 4 . For syntheses of modhephene, see:; M. Karpf and A. S. Dreiding, Tetrahedron Lett., 1980, 21, 4569-4570; A. B. Smith III and P. J. Jerris, J. Am. Chem. Soc, 1981, 103. 194-195; L. A. Paquette and H. Schostarez, J. Am. Chem. Soc., 1981, 103, 722-724; W. Oppolzer and F. Marazza, Helv. Chim. Acta. 1981, 64, 1575-1578; W. Oppolzer and K. Baettig, Hely. Chim. Acta, 1981, 64, 2489-2491; J. Wrobel, K. Takahashi, V. Honkan, G. Lannoye, J. M. Cook and S. H. Bertz, J. Org. Chem., 1983, 48, 139-141; E. A. Mash, S. K. Math and C. J. Flann, Tetrahedron Lett., 1988, 29, 2147-2150; and also under ref. 3 in this paper.
46. For earlier syntheses of pentalenene, see: G. D. Annis and L. A. Paquette. J. Am. Chem. Soc., 1982, 104, 4504-4506; L. A. Raquette and G. D. Annis, J. Am. Chem. Soc., 1983, 105, 7358-7363; E. Piers and V. Karunaratne, J. Chem. Soc., Chem. Commun., 1984, 105. 959-960; E. Piers and V. Karunaratne, Can. J. Chem., 1989, 105, 160-164; D. H. Hua, J. Am. Chem. Soc., 1986, 108, 3835-3837; T. Imanishi, F. Ninbari, M. Yamashita and C. Iwata, Chem. Pharm. Bull, 1986, 34, 2268-2271: T. Imanishi, M. Yamashita, F. Ninbari, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1988, 36, 1371-1378; T. Imanishi, M. Yamashita, Y. Hirokawa, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1990, 38, 1124-1128; T. Hudlicky, M. G. Natchus and G. Sinai-Zingde, J. Org. Chem., 1987, 52, 4641-4644; T. Hudlicky, G. Sinai-Zingde, M. G. Natchus, B. C. Ranu and P. Papadopolous, Tetrahedron, 1987, 43, 5685-5721; Y. Shizuri, S. Maki, M. Ohkubo and S. Yamamura, Tetrahedron Lett., 1990, 31, 7167-7168; M. Franck-Neumann, M. Miesch and L. Gross, Tetrahedron Lett., 1992, 33, 3879-3882: M. Miesch, L. Miesch-Gross and M. Franck-Neumann, Tetrahedron, 1997, 53, 2111-2118; M. Hatanaka, F. Uena and I. Ueda, Tetrahedron Lett., 1996, 37, 89-90; M. T. Crimmins and J. A. DeLoach, J. Am. Chem Soc., 1986, 108, 800-804; Y-J. Wu and D. J. Burnell, J. Chem. Soc., Chem. Commun., 1991, 108, 764-765; Y.-J. Wu, Y.-Y. Zhu and D. J. Burnell, J. Org. Chem., 1994, 59, 104-110; see ref. 4 . For syntheses of modhephene, see:; M. Karpf and A. S. Dreiding, Tetrahedron Lett., 1980, 21, 4569-4570; A. B. Smith III and P. J. Jerris, J. Am. Chem. Soc, 1981, 103. 194-195; L. A. Paquette and H. Schostarez, J. Am. Chem. Soc., 1981, 103, 722-724; W. Oppolzer and F. Marazza, Helv. Chim. Acta. 1981, 64, 1575-1578; W. Oppolzer and K. Baettig, Hely. Chim. Acta, 1981, 64, 2489-2491; J. Wrobel, K. Takahashi, V. Honkan, G. Lannoye, J. M. Cook and S. H. Bertz, J. Org. Chem., 1983, 48, 139-141; E. A. Mash, S. K. Math and C. J. Flann, Tetrahedron Lett., 1988, 29, 2147-2150; and also under ref. 3 in this paper.
47. For earlier syntheses of pentalenene, see: G. D. Annis and L. A. Paquette. J. Am. Chem. Soc., 1982, 104, 4504-4506; L. A. Raquette and G. D. Annis, J. Am. Chem. Soc., 1983, 105, 7358-7363; E. Piers and V. Karunaratne, J. Chem. Soc., Chem. Commun., 1984, 105. 959-960; E. Piers and V. Karunaratne, Can. J. Chem., 1989, 105, 160-164; D. H. Hua, J. Am. Chem. Soc., 1986, 108, 3835-3837; T. Imanishi, F. Ninbari, M. Yamashita and C. Iwata, Chem. Pharm. Bull, 1986, 34, 2268-2271: T. Imanishi, M. Yamashita, F. Ninbari, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1988, 36, 1371-1378; T. Imanishi, M. Yamashita, Y. Hirokawa, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1990, 38, 1124-1128; T. Hudlicky, M. G. Natchus and G. Sinai-Zingde, J. Org. Chem., 1987, 52, 4641-4644; T. Hudlicky, G. Sinai-Zingde, M. G. Natchus, B. C. Ranu and P. Papadopolous, Tetrahedron, 1987, 43, 5685-5721; Y. Shizuri, S. Maki, M. Ohkubo and S. Yamamura, Tetrahedron Lett., 1990, 31, 7167-7168; M. Franck-Neumann, M. Miesch and L. Gross, Tetrahedron Lett., 1992, 33, 3879-3882: M. Miesch, L. Miesch-Gross and M. Franck-Neumann, Tetrahedron, 1997, 53, 2111-2118; M. Hatanaka, F. Uena and I. Ueda, Tetrahedron Lett., 1996, 37, 89-90; M. T. Crimmins and J. A. DeLoach, J. Am. Chem Soc., 1986, 108, 800-804; Y-J. Wu and D. J. Burnell, J. Chem. Soc., Chem. Commun., 1991, 108, 764-765; Y.-J. Wu, Y.-Y. Zhu and D. J. Burnell, J. Org. Chem., 1994, 59, 104-110; see ref. 4 . For syntheses of modhephene, see:; M. Karpf and A. S. Dreiding, Tetrahedron Lett., 1980, 21, 4569-4570; A. B. Smith III and P. J. Jerris, J. Am. Chem. Soc, 1981, 103. 194-195; L. A. Paquette and H. Schostarez, J. Am. Chem. Soc., 1981, 103, 722-724; W. Oppolzer and F. Marazza, Helv. Chim. Acta. 1981, 64, 1575-1578; W. Oppolzer and K. Baettig, Hely. Chim. Acta, 1981, 64, 2489-2491; J. Wrobel, K. Takahashi, V. Honkan, G. Lannoye, J. M. Cook and S. H. Bertz, J. Org. Chem., 1983, 48, 139-141; E. A. Mash, S. K. Math and C. J. Flann, Tetrahedron Lett., 1988, 29, 2147-2150; and also under ref. 3 in this paper.
48. For earlier syntheses of pentalenene, see: G. D. Annis and L. A. Paquette. J. Am. Chem. Soc., 1982, 104, 4504-4506; L. A. Raquette and G. D. Annis, J. Am. Chem. Soc., 1983, 105, 7358-7363; E. Piers and V. Karunaratne, J. Chem. Soc., Chem. Commun., 1984, 105. 959-960; E. Piers and V. Karunaratne, Can. J. Chem., 1989, 105, 160-164; D. H. Hua, J. Am. Chem. Soc., 1986, 108, 3835-3837; T. Imanishi, F. Ninbari, M. Yamashita and C. Iwata, Chem. Pharm. Bull, 1986, 34, 2268-2271: T. Imanishi, M. Yamashita, F. Ninbari, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1988, 36, 1371-1378; T. Imanishi, M. Yamashita, Y. Hirokawa, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1990, 38, 1124-1128; T. Hudlicky, M. G. Natchus and G. Sinai-Zingde, J. Org. Chem., 1987, 52, 4641-4644; T. Hudlicky, G. Sinai-Zingde, M. G. Natchus, B. C. Ranu and P. Papadopolous, Tetrahedron, 1987, 43, 5685-5721; Y. Shizuri, S. Maki, M. Ohkubo and S. Yamamura, Tetrahedron Lett., 1990, 31, 7167-7168; M. Franck-Neumann, M. Miesch and L. Gross, Tetrahedron Lett., 1992, 33, 3879-3882: M. Miesch, L. Miesch-Gross and M. Franck-Neumann, Tetrahedron, 1997, 53, 2111-2118; M. Hatanaka, F. Uena and I. Ueda, Tetrahedron Lett., 1996, 37, 89-90; M. T. Crimmins and J. A. DeLoach, J. Am. Chem Soc., 1986, 108, 800-804; Y-J. Wu and D. J. Burnell, J. Chem. Soc., Chem. Commun., 1991, 108, 764-765; Y.-J. Wu, Y.-Y. Zhu and D. J. Burnell, J. Org. Chem., 1994, 59, 104-110; see ref. 4 . For syntheses of modhephene, see:; M. Karpf and A. S. Dreiding, Tetrahedron Lett., 1980, 21, 4569-4570; A. B. Smith III and P. J. Jerris, J. Am. Chem. Soc, 1981, 103. 194-195; L. A. Paquette and H. Schostarez, J. Am. Chem. Soc., 1981, 103, 722-724; W. Oppolzer and F. Marazza, Helv. Chim. Acta. 1981, 64, 1575-1578; W. Oppolzer and K. Baettig, Hely. Chim. Acta, 1981, 64, 2489-2491; J. Wrobel, K. Takahashi, V. Honkan, G. Lannoye, J. M. Cook and S. H. Bertz, J. Org. Chem., 1983, 48, 139-141; E. A. Mash, S. K. Math and C. J. Flann, Tetrahedron Lett., 1988, 29, 2147-2150; and also under ref. 3 in this paper.
49. For earlier syntheses of pentalenene, see: G. D. Annis and L. A. Paquette. J. Am. Chem. Soc., 1982, 104, 4504-4506; L. A. Raquette and G. D. Annis, J. Am. Chem. Soc., 1983, 105, 7358-7363; E. Piers and V. Karunaratne, J. Chem. Soc., Chem. Commun., 1984, 105. 959-960; E. Piers and V. Karunaratne, Can. J. Chem., 1989, 105, 160-164; D. H. Hua, J. Am. Chem. Soc., 1986, 108, 3835-3837; T. Imanishi, F. Ninbari, M. Yamashita and C. Iwata, Chem. Pharm. Bull, 1986, 34, 2268-2271: T. Imanishi, M. Yamashita, F. Ninbari, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1988, 36, 1371-1378; T. Imanishi, M. Yamashita, Y. Hirokawa, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1990, 38, 1124-1128; T. Hudlicky, M. G. Natchus and G. Sinai-Zingde, J. Org. Chem., 1987, 52, 4641-4644; T. Hudlicky, G. Sinai-Zingde, M. G. Natchus, B. C. Ranu and P. Papadopolous, Tetrahedron, 1987, 43, 5685-5721; Y. Shizuri, S. Maki, M. Ohkubo and S. Yamamura, Tetrahedron Lett., 1990, 31, 7167-7168; M. Franck-Neumann, M. Miesch and L. Gross, Tetrahedron Lett., 1992, 33, 3879-3882: M. Miesch, L. Miesch-Gross and M. Franck-Neumann, Tetrahedron, 1997, 53, 2111-2118; M. Hatanaka, F. Uena and I. Ueda, Tetrahedron Lett., 1996, 37, 89-90; M. T. Crimmins and J. A. DeLoach, J. Am. Chem Soc., 1986, 108, 800-804; Y-J. Wu and D. J. Burnell, J. Chem. Soc., Chem. Commun., 1991, 108, 764-765; Y.-J. Wu, Y.-Y. Zhu and D. J. Burnell, J. Org. Chem., 1994, 59, 104-110; see ref. 4 . For syntheses of modhephene, see:; M. Karpf and A. S. Dreiding, Tetrahedron Lett., 1980, 21, 4569-4570; A. B. Smith III and P. J. Jerris, J. Am. Chem. Soc, 1981, 103. 194-195; L. A. Paquette and H. Schostarez, J. Am. Chem. Soc., 1981, 103, 722-724; W. Oppolzer and F. Marazza, Helv. Chim. Acta. 1981, 64, 1575-1578; W. Oppolzer and K. Baettig, Hely. Chim. Acta, 1981, 64, 2489-2491; J. Wrobel, K. Takahashi, V. Honkan, G. Lannoye, J. M. Cook and S. H. Bertz, J. Org. Chem., 1983, 48, 139-141; E. A. Mash, S. K. Math and C. J. Flann, Tetrahedron Lett., 1988, 29, 2147-2150; and also under ref. 3 in this paper.
50. For earlier syntheses of pentalenene, see: G. D. Annis and L. A. Paquette. J. Am. Chem. Soc., 1982, 104, 4504-4506; L. A. Raquette and G. D. Annis, J. Am. Chem. Soc., 1983, 105, 7358-7363; E. Piers and V. Karunaratne, J. Chem. Soc., Chem. Commun., 1984, 105. 959-960; E. Piers and V. Karunaratne, Can. J. Chem., 1989, 105, 160-164; D. H. Hua, J. Am. Chem. Soc., 1986, 108, 3835-3837; T. Imanishi, F. Ninbari, M. Yamashita and C. Iwata, Chem. Pharm. Bull, 1986, 34, 2268-2271: T. Imanishi, M. Yamashita, F. Ninbari, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1988, 36, 1371-1378; T. Imanishi, M. Yamashita, Y. Hirokawa, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1990, 38, 1124-1128; T. Hudlicky, M. G. Natchus and G. Sinai-Zingde, J. Org. Chem., 1987, 52, 4641-4644; T. Hudlicky, G. Sinai-Zingde, M. G. Natchus, B. C. Ranu and P. Papadopolous, Tetrahedron, 1987, 43, 5685-5721; Y. Shizuri, S. Maki, M. Ohkubo and S. Yamamura, Tetrahedron Lett., 1990, 31, 7167-7168; M. Franck-Neumann, M. Miesch and L. Gross, Tetrahedron Lett., 1992, 33, 3879-3882: M. Miesch, L. Miesch-Gross and M. Franck-Neumann, Tetrahedron, 1997, 53, 2111-2118; M. Hatanaka, F. Uena and I. Ueda, Tetrahedron Lett., 1996, 37, 89-90; M. T. Crimmins and J. A. DeLoach, J. Am. Chem Soc., 1986, 108, 800-804; Y-J. Wu and D. J. Burnell, J. Chem. Soc., Chem. Commun., 1991, 108, 764-765; Y.-J. Wu, Y.-Y. Zhu and D. J. Burnell, J. Org. Chem., 1994, 59, 104-110; see ref. 4 . For syntheses of modhephene, see:; M. Karpf and A. S. Dreiding, Tetrahedron Lett., 1980, 21, 4569-4570; A. B. Smith III and P. J. Jerris, J. Am. Chem. Soc, 1981, 103. 194-195; L. A. Paquette and H. Schostarez, J. Am. Chem. Soc., 1981, 103, 722-724; W. Oppolzer and F. Marazza, Helv. Chim. Acta. 1981, 64, 1575-1578; W. Oppolzer and K. Baettig, Hely. Chim. Acta, 1981, 64, 2489-2491; J. Wrobel, K. Takahashi, V. Honkan, G. Lannoye, J. M. Cook and S. H. Bertz, J. Org. Chem., 1983, 48, 139-141; E. A. Mash, S. K. Math and C. J. Flann, Tetrahedron Lett., 1988, 29, 2147-2150; and also under ref. 3 in this paper.
51. For earlier syntheses of pentalenene, see: G. D. Annis and L. A. Paquette. J. Am. Chem. Soc., 1982, 104, 4504-4506; L. A. Raquette and G. D. Annis, J. Am. Chem. Soc., 1983, 105, 7358-7363; E. Piers and V. Karunaratne, J. Chem. Soc., Chem. Commun., 1984, 105. 959-960; E. Piers and V. Karunaratne, Can. J. Chem., 1989, 105, 160-164; D. H. Hua, J. Am. Chem. Soc., 1986, 108, 3835-3837; T. Imanishi, F. Ninbari, M. Yamashita and C. Iwata, Chem. Pharm. Bull, 1986, 34, 2268-2271: T. Imanishi, M. Yamashita, F. Ninbari, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1988, 36, 1371-1378; T. Imanishi, M. Yamashita, Y. Hirokawa, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1990, 38, 1124-1128; T.
52. For earlier syntheses of pentalenene, see: G. D. Annis and L. A. Paquette. J. Am. Chem. Soc., 1982, 104, 4504-4506; L. A. Raquette and G. D. Annis, J. Am. Chem. Soc., 1983, 105, 7358-7363; E. Piers and V. Karunaratne, J. Chem. Soc., Chem. Commun., 1984, 105. 959-960; E. Piers and V. Karunaratne, Can. J. Chem., 1989, 105, 160-164; D. H. Hua, J. Am. Chem. Soc., 1986, 108, 3835-3837; T. Imanishi, F. Ninbari, M. Yamashita and C. Iwata, Chem. Pharm. Bull, 1986, 34, 2268-2271: T. Imanishi, M. Yamashita, F. Ninbari, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1988, 36, 1371-1378; T. Imanishi, M. Yamashita, Y. Hirokawa, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1990, 38, 1124-1128; T. Hudlicky, M. G. Natchus and G. Sinai-Zingde, J. Org. Chem., 1987, 52, 4641-4644; T. Hudlicky, G. Sinai-Zingde, M. G. Natchus, B. C. Ranu and P. Papadopolous, Tetrahedron, 1987, 43, 5685-5721; Y. Shizuri, S. Maki, M. Ohkubo and S. Yamamura, Tetrahedron Lett., 1990, 31, 7167-7168; M. Franck-Neumann, M. Miesch and L. Gross, Tetrahedron Lett., 1992, 33, 3879-3882: M. Miesch, L. Miesch-Gross and M. Franck-Neumann, Tetrahedron, 1997, 53, 2111-2118; M. Hatanaka, F. Uena and I. Ueda, Tetrahedron Lett., 1996, 37, 89-90; M. T. Crimmins and J. A. DeLoach, J. Am. Chem Soc., 1986, 108, 800-804; Y-J. Wu and D. J. Burnell, J. Chem. Soc., Chem. Commun., 1991, 108, 764-765; Y.-J. Wu, Y.-Y. Zhu and D. J. Burnell, J. Org. Chem., 1994, 59, 104-110; see ref. 4 . For syntheses of modhephene, see:; M. Karpf and A. S. Dreiding, Tetrahedron Lett., 1980, 21, 4569-4570; A. B. Smith III and P. J. Jerris, J. Am. Chem. Soc, 1981, 103. 194-195; L. A. Paquette and H. Schostarez, J. Am. Chem. Soc., 1981, 103, 722-724; W. Oppolzer and F. Marazza, Helv. Chim. Acta. 1981, 64, 1575-1578; W. Oppolzer and K. Baettig, Hely. Chim. Acta, 1981, 64, 2489-2491; J. Wrobel, K. Takahashi, V. Honkan, G. Lannoye, J. M. Cook and S. H. Bertz, J. Org. Chem., 1983, 48, 139-141; E. A. Mash, S. K. Math and C. J. Flann, Tetrahedron Lett., 1988, 29, 2147-2150; and also under ref. 3 in this paper.
53. For earlier syntheses of pentalenene, see: G. D. Annis and L. A. Paquette. J. Am. Chem. Soc., 1982, 104, 4504-4506; L. A. Raquette and G. D. Annis, J. Am. Chem. Soc., 1983, 105, 7358-7363; E. Piers and V. Karunaratne, J. Chem. Soc., Chem. Commun., 1984, 105. 959-960; E. Piers and V. Karunaratne, Can. J. Chem., 1989, 105, 160-164; D. H. Hua, J. Am. Chem. Soc., 1986, 108, 3835-3837; T. Imanishi, F. Ninbari, M. Yamashita and C. Iwata, Chem. Pharm. Bull, 1986, 34, 2268-2271: T. Imanishi, M. Yamashita, F. Ninbari, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1988, 36, 1371-1378; T. Imanishi, M. Yamashita, Y. Hirokawa, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1990, 38, 1124-1128; T. Hudlicky, M. G. Natchus and G. Sinai-Zingde, J. Org. Chem., 1987, 52, 4641-4644; T. Hudlicky, G. Sinai-Zingde, M. G. Natchus, B. C. Ranu and P. Papadopolous, Tetrahedron, 1987, 43, 5685-5721; Y. Shizuri, S. Maki, M. Ohkubo and S. Yamamura, Tetrahedron Lett., 1990, 31, 7167-7168; M. Franck-Neumann, M. Miesch and L. Gross, Tetrahedron Lett., 1992, 33, 3879-3882: M. Miesch, L. Miesch-Gross and M. Franck-Neumann, Tetrahedron, 1997, 53, 2111-2118; M. Hatanaka, F. Uena and I. Ueda, Tetrahedron Lett., 1996, 37, 89-90; M. T. Crimmins and J. A. DeLoach, J. Am. Chem Soc., 1986, 108, 800-804; Y-J. Wu and D. J. Burnell, J. Chem. Soc., Chem. Commun., 1991, 108, 764-765; Y.-J. Wu, Y.-Y. Zhu and D. J. Burnell, J. Org. Chem., 1994, 59, 104-110; see ref. 4 . For syntheses of modhephene, see:; M. Karpf and A. S. Dreiding, Tetrahedron Lett., 1980, 21, 4569-4570; A. B. Smith III and P. J. Jerris, J. Am. Chem. Soc, 1981, 103. 194-195; L. A. Paquette and H. Schostarez, J. Am. Chem. Soc., 1981, 103, 722-724; W. Oppolzer and F. Marazza, Helv. Chim. Acta. 1981, 64, 1575-1578; W. Oppolzer and K. Baettig, Hely. Chim. Acta, 1981, 64, 2489-2491; J. Wrobel, K. Takahashi, V. Honkan, G. Lannoye, J. M. Cook and S. H. Bertz, J. Org. Chem., 1983, 48, 139-141; E. A. Mash, S. K. Math and C. J. Flann, Tetrahedron Lett., 1988, 29, 2147-2150; and also under ref. 3 in this paper.
54. For earlier syntheses of pentalenene, see: G. D. Annis and L. A. Paquette. J. Am. Chem. Soc., 1982, 104, 4504-4506; L. A. Raquette and G. D. Annis, J. Am. Chem. Soc., 1983, 105, 7358-7363; E. Piers and V. Karunaratne, J. Chem. Soc., Chem. Commun., 1984, 105. 959-960; E. Piers and V. Karunaratne, Can. J. Chem., 1989, 105, 160-164; D. H. Hua, J. Am. Chem. Soc., 1986, 108, 3835-3837; T. Imanishi, F. Ninbari, M. Yamashita and C. Iwata, Chem. Pharm. Bull, 1986, 34, 2268-2271: T. Imanishi, M. Yamashita, F. Ninbari, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1988, 36, 1371-1378; T. Imanishi, M. Yamashita, Y. Hirokawa, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1990, 38, 1124-1128; T. Hudlicky, M. G. Natchus and G. Sinai-Zingde, J. Org. Chem., 1987, 52, 4641-4644; T. Hudlicky, G. Sinai-Zingde, M. G. Natchus, B. C. Ranu and P. Papadopolous, Tetrahedron, 1987, 43, 5685-5721; Y. Shizuri, S. Maki, M. Ohkubo and S. Yamamura, Tetrahedron Lett., 1990, 31, 7167-7168; M. Franck-Neumann, M. Miesch and L. Gross, Tetrahedron Lett., 1992, 33, 3879-3882: M. Miesch, L. Miesch-Gross and M. Franck-Neumann, Tetrahedron, 1997, 53, 2111-2118; M. Hatanaka, F. Uena and I. Ueda, Tetrahedron Lett., 1996, 37, 89-90; M. T. Crimmins and J. A. DeLoach, J. Am. Chem Soc., 1986, 108, 800-804; Y-J. Wu and D. J. Burnell, J. Chem. Soc., Chem. Commun., 1991, 108, 764-765; Y.-J. Wu, Y.-Y. Zhu and D. J. Burnell, J. Org. Chem., 1994, 59, 104-110; see ref. 4 . For syntheses of modhephene, see:; M. Karpf and A. S. Dreiding, Tetrahedron Lett., 1980, 21, 4569-4570; A. B. Smith III and P. J. Jerris, J. Am. Chem. Soc, 1981, 103. 194-195; L. A. Paquette and H. Schostarez, J. Am. Chem. Soc., 1981, 103, 722-724; W. Oppolzer and F. Marazza, Helv. Chim. Acta. 1981, 64, 1575-1578; W. Oppolzer and K. Baettig, Hely. Chim. Acta, 1981, 64, 2489-2491; J. Wrobel, K. Takahashi, V. Honkan, G. Lannoye, J. M. Cook and S. H. Bertz, J. Org. Chem., 1983, 48, 139-141; E. A. Mash, S. K. Math and C. J. Flann, Tetrahedron Lett., 1988, 29, 2147-2150; and also under ref. 3 in this paper.
55. For earlier syntheses of pentalenene, see: G. D. Annis and L. A. Paquette. J. Am. Chem. Soc., 1982, 104, 4504-4506; L. A. Raquette and G. D. Annis, J. Am. Chem. Soc., 1983, 105, 7358-7363; E. Piers and V. Karunaratne, J. Chem. Soc., Chem. Commun., 1984, 105. 959-960; E. Piers and V. Karunaratne, Can. J. Chem., 1989, 105, 160-164; D. H. Hua, J. Am. Chem. Soc., 1986, 108, 3835-3837; T. Imanishi, F. Ninbari, M. Yamashita and C. Iwata, Chem. Pharm. Bull, 1986, 34, 2268-2271: T. Imanishi, M. Yamashita, F. Ninbari, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1988, 36, 1371-1378; T. Imanishi, M. Yamashita, Y. Hirokawa, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1990, 38, 1124-1128; T. Hudlicky, M. G. Natchus and G. Sinai-Zingde, J. Org. Chem., 1987, 52, 4641-4644; T. Hudlicky, G. Sinai-Zingde, M. G. Natchus, B. C. Ranu and P. Papadopolous, Tetrahedron, 1987, 43, 5685-5721; Y. Shizuri, S. Maki, M. Ohkubo and S. Yamamura, Tetrahedron Lett., 1990, 31, 7167-7168; M. Franck-Neumann, M. Miesch and L. Gross, Tetrahedron Lett., 1992, 33, 3879-3882: M. Miesch, L. Miesch-Gross and M. Franck-Neumann, Tetrahedron, 1997, 53, 2111-2118; M. Hatanaka, F. Uena and I. Ueda, Tetrahedron Lett., 1996, 37, 89-90; M. T. Crimmins and J. A. DeLoach, J. Am. Chem Soc., 1986, 108, 800-804; Y-J. Wu and D. J. Burnell, J. Chem. Soc., Chem. Commun., 1991, 108, 764-765; Y.-J. Wu, Y.-Y. Zhu and D. J. Burnell, J. Org. Chem., 1994, 59, 104-110; see ref. 4 . For syntheses of modhephene, see:; M. Karpf and A. S. Dreiding, Tetrahedron Lett., 1980, 21, 4569-4570; A. B. Smith III and P. J. Jerris, J. Am. Chem. Soc, 1981, 103. 194-195; L. A. Paquette and H. Schostarez, J. Am. Chem. Soc., 1981, 103, 722-724; W. Oppolzer and F. Marazza, Helv. Chim. Acta. 1981, 64, 1575-1578; W. Oppolzer and K. Baettig, Hely. Chim. Acta, 1981, 64, 2489-2491; J. Wrobel, K. Takahashi, V. Honkan, G. Lannoye, J. M. Cook and S. H. Bertz, J. Org. Chem., 1983, 48, 139-141; E. A. Mash, S. K. Math and C. J. Flann, Tetrahedron Lett., 1988, 29, 2147-2150; and also under ref. 3 in this paper.
56. For earlier syntheses of pentalenene, see: G. D. Annis and L. A. Paquette. J. Am. Chem. Soc., 1982, 104, 4504-4506; L. A. Raquette and G. D. Annis, J. Am. Chem. Soc., 1983, 105, 7358-7363; E. Piers and V. Karunaratne, J. Chem. Soc., Chem. Commun., 1984, 105. 959-960; E. Piers and V. Karunaratne, Can. J. Chem., 1989, 105, 160-164; D. H. Hua, J. Am. Chem. Soc., 1986, 108, 3835-3837; T. Imanishi, F. Ninbari, M. Yamashita and C. Iwata, Chem. Pharm. Bull, 1986, 34, 2268-2271: T. Imanishi, M. Yamashita, F. Ninbari, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1988, 36, 1371-1378; T. Imanishi, M. Yamashita, Y. Hirokawa, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1990, 38, 1124-1128; T. Hudlicky, M. G. Natchus and G. Sinai-Zingde, J. Org. Chem., 1987, 52, 4641-4644; T. Hudlicky, G. Sinai-Zingde, M. G. Natchus, B. C. Ranu and P. Papadopolous, Tetrahedron, 1987, 43, 5685-5721; Y. Shizuri, S. Maki, M. Ohkubo and S. Yamamura, Tetrahedron Lett., 1990, 31, 7167-7168; M. Franck-Neumann, M. Miesch and L. Gross, Tetrahedron Lett., 1992, 33, 3879-3882: M. Miesch, L. Miesch-Gross and M. Franck-Neumann, Tetrahedron, 1997, 53, 2111-2118; M. Hatanaka, F. Uena and I. Ueda, Tetrahedron Lett., 1996, 37, 89-90; M. T. Crimmins and J. A. DeLoach, J. Am. Chem Soc., 1986, 108, 800-804; Y-J. Wu and D. J. Burnell, J. Chem. Soc., Chem. Commun., 1991, 108, 764-765; Y.-J. Wu, Y.-Y. Zhu and D. J. Burnell, J. Org. Chem., 1994, 59, 104-110; see ref. 4 . For syntheses of modhephene, see:; M. Karpf and A. S. Dreiding, Tetrahedron Lett., 1980, 21, 4569-4570; A. B. Smith III and P. J. Jerris, J. Am. Chem. Soc, 1981, 103. 194-195; L. A. Paquette and H. Schostarez, J. Am. Chem. Soc., 1981, 103, 722-724; W. Oppolzer and F. Marazza, Helv. Chim. Acta. 1981, 64, 1575-1578; W. Oppolzer and K. Baettig, Hely. Chim. Acta, 1981, 64, 2489-2491; J. Wrobel, K. Takahashi, V. Honkan, G. Lannoye, J. M. Cook and S. H. Bertz, J. Org. Chem., 1983, 48, 139-141; E. A. Mash, S. K. Math and C. J. Flann, Tetrahedron Lett., 1988, 29, 2147-2150; and also under ref. 3 in this paper.
57. For earlier syntheses of pentalenene, see: G. D. Annis and L. A. Paquette. J. Am. Chem. Soc., 1982, 104, 4504-4506; L. A. Raquette and G. D. Annis, J. Am. Chem. Soc., 1983, 105, 7358-7363; E. Piers and V. Karunaratne, J. Chem. Soc., Chem. Commun., 1984, 105. 959-960; E. Piers and V. Karunaratne, Can. J. Chem., 1989, 105, 160-164; D. H. Hua, J. Am. Chem. Soc., 1986, 108, 3835-3837; T. Imanishi, F. Ninbari, M. Yamashita and C. Iwata, Chem. Pharm. Bull, 1986, 34, 2268-2271: T. Imanishi, M. Yamashita, F. Ninbari, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1988, 36, 1371-1378; T. Imanishi, M. Yamashita, Y. Hirokawa, T. Tanaka and C. Iwata, Chem. Pharm. Bull., 1990, 38, 1124-1128; T. Hudlicky, M. G. Natchus and G. Sinai-Zingde, J. Org. Chem., 1987, 52, 4641-4644; T. Hudlicky, G. Sinai-Zingde, M. G. Natchus, B. C. Ranu and P. Papadopolous, Tetrahedron, 1987, 43, 5685-5721; Y. Shizuri, S. Maki, M. Ohkubo and S. Yamamura, Tetrahedron Lett., 1990, 31, 7167-7168; M. Franck-Neumann, M. Miesch and L. Gross, Tetrahedron Lett., 1992, 33, 3879-3882: M. Miesch, L. Miesch-Gross and M. Franck-Neumann, Tetrahedron, 1997, 53, 2111-2118; M. Hatanaka, F. Uena and I. Ueda, Tetrahedron Lett., 1996, 37, 89-90; M. T. Crimmins and J. A. DeLoach, J. Am. Chem Soc., 1986, 108, 800-804; Y-J. Wu and D. J. Burnell, J. Chem. Soc., Chem. Commun., 1991, 108, 764-765; Y.-J. Wu, Y.-Y. Zhu and D. J. Burnell, J. Org. Chem., 1994, 59, 104-110; see ref. 4 . For syntheses of modhephene, see:; M. Karpf and A. S. Dreiding, Tetrahedron Lett., 1980, 21, 4569-4570; A. B. Smith III and P. J. Jerris, J. Am. Chem. Soc, 1981, 103. 194-195; L. A. Paquette and H. Schostarez, J. Am. Chem. Soc., 1981, 103, 722-724; W. Oppolzer and F. Marazza, Helv. Chim. Acta. 1981, 64, 1575-1578; W. Oppolzer and K. Baettig, Hely. Chim. Acta, 1981, 64, 2489-2491; J. Wrobel, K. Takahashi, V. Honkan, G. Lannoye, J. M. Cook and S. H. Bertz, J. Org. Chem., 1983, 48, 139-141; E. A. Mash, S. K. Math and C. J. Flann, Tetrahedron Lett., 1988, 29, 2147-2150; and also under ref. 3 in this paper.
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