Solvent and substituent effects in the periselectivity of the staudinger reaction between ketenes and α,β-unsaturated imines. A theoretical and experimental study

Journal of Organic Chemistry

Volumn 61, Issue 9, 1996, Pages 3070-3079

  Lecea, Begoña ^a   Arrastia, Iosune ^a   Arrieta, Ana ^a   Roa, Guillermo ^a   Lopez, Xabier ^a   Arriortua, M Isabel ^a   Ugalde, Jesus M ^a   Cossío, Fernando P ^a  

^a UNIVERSITY OF THE BASQUE COUNTRY UPV EHU   (Spain)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0001176231     PISSN: 00223263     EISSN: None     Source Type: Journal    
DOI: 10.1021/jo951867w     Document Type: Article

References (106)

1. Tidwell, T. T. Ketenes; Wiley: New York, 1995; pp 459-571.
2. (a) Woodward, R. B.; Hoffmann, R. The Conservation of Orbital Symmetry; Verlag Press: New York, 1969.
3. (b) Houk, K. N.; Strozier, R. W.; Hall, J. A. Tetrahedron Lett. 1974, 897.
4. (c) Ghosez, L.; O'Donnell, M. J. Pericyclic Reactions; Marchand, A. P., Lehr, R. E., Eds.; Academic Press: New York, 1977; Vol. 3, pp 79-140.
5. (a) Valentí, E.; Pericàs, M. A.; Moyano, A. J. Org. Chem. 1990, 55, 3582.
6. (b) Wang, X.; Houk, K. N. J. Am. Chem. Soc. 1990, 112, 1754.
7. (c) Yamabe, S.; Minato, T.; Osamura, Y. J. Chem. Soc., Chem. Commun. 1993, 450.
8. For stepwise reaction paths see ref 3a and: (d) Bernardi, F.; Bottoni, A.; Robb, M. A.; Venturini, A. J. Am. Chem. Soc. 1990, 112, 2106.
9. (a) Lecea, B.; Arrieta, A.; Roa, G.; Ugalde, J. M.; Cossío, F. P. J. Am. Chem. Soc. 1994, 116, 9613.
10. (b) Krabbenhoft, H. O. J. Org. Chem. 1978, 43, 1305.
11. (a) Baldwin, J. E.; Kapecki, J. A. J. Am. Chem. Soc. 1970, 92, 4874.
12. (b) Pasto, D. J. J. Am. Chem. Soc. 1979, 101, 37.
13. Staudinger, H. Liebigs Ann.Chem. 1907, 356, 51.
14. (a) Hegedus, L. S.; Montgomery, J.; Narukawa, Y.; Snustad, D. C. J. Am. Chem. Soc. 1991, 113, 5784.
15. (b) Georg, G. L.; Ravikumar, V. T. In The Organic Chemistry of β-Lactams; Georg, G. L., Ed.; Verlag Chemie: New York, 1993; pp 295-381.
16. (a) Cossío, F. P.; Ugalde, J. M.; Lopez, X.; Lecea, B.; Palomo, C. J. Am. Chem. Soc. 1993, 115, 995.
17. (b) Cossío, F. P.; Arrieta, A.; Lecea, B.; Ugalde, J. M. J. Am. Chem. Soc. 1994, 116, 2085.
18. (c) Arrieta, A.; Ugalde, J. M.; Cossío, F. P.; Lecea, B. Tetrahedron Lett. 1994, 35, 4465.
19. (d) Arrastia, I.; Arrieta, A.; Ugalde, J. M.; Cossío, F. P., Lecea, B. Tetrahedron Lett. 1994, 35, 7825.
20. (a) Sordo, J. A.; González, J.; Sordo, T. L. J. Am. Chem. Soc. 1992, 114, 6249.
21. (b) López, R.; Sordo, T. L.; Sordo, J. A.; González, J. J. Org. Chem. 1993, 58, 7036.
22. (c) Assfeld, X.; Sordo, J. A.; González, J.; Ruiz-López, M. F.; Sordo, T. L. THEOCHEM 1993, 287, 193.
23. (d) Assfeld, X.; Ruiz-López; M. F.; ; González, J.; López, R.; Sordo, J. A.; Sordo, T. L. J. Comput.Chem. 1994, 15, 479.
24. (a) Boyd, D. B. Computer-Assisted Molecular Design Studies of β-Lactam Antibiotics. In Frontiers on Antibiotic Research; Umezawa, H., Ed.; Academic Press: Tokyo, 1987; pp 339-356.
25. (b) Cooper, R. D. G.; Daugherty, B. W.; Boyd, D. B. Pure Appl. Chem. 1987, 59, 485.
26. (a) Ghosez, L.; Marchand-Brynaert, J. In Comprehensive Organic Synthesis; Trost, B., Fleming, I., Eds.; Pergamon: Oxford, 1991; Vol. 5, pp 85-122.
27. (b) Thomas, R. C. In Recent Progress in the Chemical Synthesis of Antibiotics; Lukacs, G., Ohno, M., Eds.; Springer-Verlag: Berlin, 1989; p 533.
28. (c) Van der Steen, F. H.; Van Koten, G. Tetrahedron 1991, 47, 7503.
29. (d) Backes, I. In Methoden der Organischen Chemie; Kalgman, D., Ed.; Georg Thieme: Stuttgart, 1991; Vol. E15b, Organische Stickstoffverbindungen II, pp 383-483.
30. (e) Oligaruso, M. A.; Wolfe, J. F. In Synthesis of Lactones-Updates from the Chemistry of Functional Groups; Patai, S., Rappoport, Z., Eds.; Wiley: Chichester, 1993; pp 168-268 and 490-623.
31. Dumas, S.; Hegedus, L. S. J. Org. Chem. 1994, 59, 4967.
32. Pfleger, R.; Jäger, A. Chem. Ber. 1957, 90, 2460.
33. Hull, R. J. Chem. Soc. C 1967, 1154.
34. Gompper, R. Angew. Chem., Int. Ed. Engl. 1969, 8, 312.
35. Duran, F.; Ghosez, L. Tetrahedron Lett. 1970, 245.
36. Sakamoto, M.; Tomimatsu, Y. Yakugaku Zasshi 1970, 90, 1386; C. A.
37. Komatsu, M.; Yamamoto, S.; Ohshiro, Y.; Agawa, T. Tetrahedron Lett. 1981, 22, 3769 and ref 4 and 5 therein.
38. Moore, H. W.; Hughes, G. Tetrahedron Lett. 1982, 23, 4003.
39. Brady, W. T.; Shiem, C. H. J. Org. Chem. 1983, 48, 2499.
40. Moore, H. W.; Hughes, G.; Srinivasachar, K.; Fernandez, M.; Nguyen, N. V.; Schoon, D.; Tranne, A. J. Org. Chem. 1985, 50, 4231.
41. Palomo, C.; Cossío, F. P.; Odriozola, J. M.; Oiarbide, M.; Ontoria, J. M. J. Org. Chem. 1991, 56, 4418.
42. Chemistry and Biology of β-Lactam Antibiotics; Morin, R. B., Gorman, M., Eds.; Academic Press: New York, 1982; Vols. 1-3.
43. Kant, J.; Walker, D. G. In The Organic Chemistry of β-Lactams; Georg, G. I., Ed.; Verlag Chemie: New York, 1993; pp 121-196.
44. Dewar, M. J. S.; Zoebisch, E. G.; Healy, E. F.; Stewart, J. J. P. J. Am. Chem. Soc. 1985, 107, 3902.
45. Dewar, M. J. S.; Zoebisch, E. G. THEOCHEM 1988, 180, 1.
46. (a) Stewart, J. J. P. QCPE Bull. 1983, 3, 101.
47. (b) QCPE No. 455; Indiana University, Bloomington, IN.
48. Bartels, R. H. Report CNA-44; University of Texas; Center for Numerical Analysis: Austin, TX, 1972.
49. Baker, J. J. Comput. Chem. 1986, 7, 385.
50. Boyd, D. B.; Smith, D. W.; Stewart, J. J. P.; Wimmer, E. J. Comput. Chem. 1988, 9, 387.
51. (a) Dewar, M. J. S.; Hashnall, J. A.; Venier, C. G. J. Am. Chem. Soc. 1968, 90, 1953.
52. (b) Dewar, M. J. S.; Olivella, S. J. Chem. Soc., Faraday Trans. 2 1979, 75, 829.
53. (c) Salem, L. Pure Appl. Chem. 1973, 33, 317.
54. Gaussian 92, Revision C: Frisch, M. J.; Trucks, G. W.; Head-Gordon, M.; Gill, P. M. W.; Wong, M. W.; Foresman, J. B.; Johnson, B. G.; Schlegel, H. B.; Robb, M. A.; Replogle, E. S.; Gomperts, R.; Andres, J. L.; Raghavachari, K.; Binkley, J. S.; Gonzalez, C.; Martin, R. L.; Fox, D. J.; Defrees, D. J.; Baker, J.; Stewart, J. J. P.; Pople, J. A. Gaussian, Inc., Pittsburgh, PA, 1992.
55. Gaussian 92/DFT, revision F.4: Frisch, M. J.; Trucks, G. W.; Schlegel, H. B.; Gill, P. M. W.; Johnson, B. G.; Wong, M. W.; Foresman, J. B.; Robb, M. A., Head-Gordon, M.; Replogle, E. S.; Gomperts, R.; Andres, J. L.; Raghavachari, K.; Binkley, J. S.; Gonzalez, C.; Martin, R. L.; Fox, D. J.; Defrees, D. J.; Baker, J.; Stewart, J. J.P.; Pople, J. A., Gaussian, Inc., Pittsburgh PA, 1993.
56. GAMESS (General Atomic and Molecular Electronic Structure System, CRAY-UNICOS Version). (a) Schmidt, M. W.; Baldridge, K. K.; Boatz, J. A.; Jensen, J. M.; Koseki, S.; Gordon, M. S.; Nguyen, K. A.; Windus, T. L.; Elbert, S. T. QCPE Bull. 1990, 10, 52. (b) Schmidt, M. W.; Baldridge, K. K.; Boatz, J. A.; Gordon, M. S.; Jensen, J. M.; Koseki, S.; Matsunaga, N.; Nguyen, K. A.; Su, S.; Windus, T. L. J. Comput. Chem. 1993, 14, 1347.
57. GAMESS (General Atomic and Molecular Electronic Structure System, CRAY-UNICOS Version). (a) Schmidt, M. W.; Baldridge, K. K.; Boatz, J. A.; Jensen, J. M.; Koseki, S.; Gordon, M. S.; Nguyen, K. A.; Windus, T. L.; Elbert, S. T. QCPE Bull. 1990, 10, 52. (b) Schmidt, M. W.; Baldridge, K. K.; Boatz, J. A.; Gordon, M. S.; Jensen, J. M.; Koseki, S.; Matsunaga, N.; Nguyen, K. A.; Su, S.; Windus, T. L. J. Comput. Chem. 1993, 14, 1347.
58. Hehre, W. J.; Radom, L.; Schleyer, P.v.R.; Pople, J. A. Ab Initio Molecular Orbital Theory; Wiley: New York, 1986; pp 65-88 and references therein.
59. McIver, J. W.; Komornicki, A. J. Am. Chem. Soc. 1972, 94, 2625.
60. Roos, B. O.; Taylor, P. R.; Siegbahn, P. E. M. Chem. Phys. 1980, 48, 157.
61. Parr, R. G.; Yang, W. Density-Functional Theory of Atoms and Molecules; Oxford: New York, 1989.
62. (a) Binkley, J. S.; Pople, J. A. Int. J. Quantum Chem. 1975, 9, 229.
63. (b) Pople, J. A.; Binkley, J. S.; Seeger, R. Int. J. Quantum Chem. Symp. 1976, 10, 1.
64. Becke, A. D. J. Chem. Phys. 1993, 98, 5648.
65. (a) Becke, A. D. Phys. Rev. A 1988, 38, 3098.
66. (b) Lee, C.; Yang, W.; Parr, R. G. Phys. Rev. B 1980, 37, 785.
67. (c) Vosko, S. H.; Wilk, L.; Nusair, M. Can. J. Phys. 1980, 58, 1200.
68. (a) Tomasi, J.; Persico, M. Chem. Rev. 1974, 94, 2027.
69. (b) Simkin, B. Ya.; Sheikhet, I. Quantum Chemical and Statistical Theory of Solutions - A Computational Approach; Ellis Horwood: London, 1995; pp 78-101.
70. (a) Wong, M. W.; Frisch, M. J.; Wiberg, K. B. J. Am. Chem. Soc. 1990, 112, 4776.
71. (b) Wong, M. W.; Wiberg, K. B.; Frisch, M. J. J. Chem. Phys 1991, 95, 8991.
72. (a) Sheehan, J. C.; Ryan, J. J. J. Am. Chem. Soc. 1951, 73, 1204.
73. (b) Mannas, M. S.; Chib, J. S.; Chiang, Y. H.; Bose, A. K. Tetrahedron 1969, 25, 4421.
74. Lynch, J. E.; Riseman, S. M.; Laswell, W. L.; Tschaen, D. M.; Volante, R. P.; Smith, G. B.; Shinkai, I. J. Org. Chem. 1989, 54, 3792.
75. Bose, A. K.; Manhas, M. S.; Van der Veen, J. M.; Amin, S. G.; Fernandez, I. F.; Gala, K.; Gruska, R.; Kapur, J. C.; Khajavi, M. S.; Kreder, J.; Mukkavilli, L.; Ram, B.; Sugiura, M.; Vincent, J. E. Tetrahedron 1981, 37, 2321.
76. Kagan, H. B.; Basselier, J. J.; Luche, J. L. Tetrahedron Lett. 1964, 941.
77. For significant examples, see: (a) Dugat, D.; Just, G.; Sahoo, S. Can. J. Chem. 1987, 65, 88. (b) Zamboni, R.; Just, G. Can. J. Chem. 1979, 57, 1945. (c) Kronenthal, D. R., Han, C. Y.; Taylor, M. K. J. Org. Chem. 1982, 47, 2765. (d) Evans, D. E.; Sjogren, E. B. Tetrahedron Lett. 1985, 26, 3783. (e) Ikota, N.; Hanaki, A. Heterocycles 1984, 22, 2227. (f) Ikota, N. Chem. Pharm. Bull. 1990, 38, 1601. (g) Borer, B. C.; Balogh, D. W. Tetrahedron Lett. 1991, 32, 1039. (h) Georg, G. I.; Akgün, E.; Mashava, P.; Milstead, M.; He, P.; Wu, Z.; Velde, D. V.; Takusagawa, F. Tetrahedron Lett. 1992, 33, 2111. (i) Georg, G. I.; Mashava, P. M.; Guan, X. Tetrahedron Lett. 1991, 32, 581. (j) Gunda, T. E.; Vieth, S.; Kover, K. E.; Sztaricskkai, F. Tetrahedron Lett. 1990, 31, 6707.
78. For significant examples, see: (a) Dugat, D.; Just, G.; Sahoo, S. Can. J. Chem. 1987, 65, 88. (b) Zamboni, R.; Just, G. Can. J. Chem. 1979, 57, 1945. (c) Kronenthal, D. R., Han, C. Y.; Taylor, M. K. J. Org. Chem. 1982, 47, 2765. (d) Evans, D. E.; Sjogren, E. B. Tetrahedron Lett. 1985, 26, 3783. (e) Ikota, N.; Hanaki, A. Heterocycles 1984, 22, 2227. (f) Ikota, N. Chem. Pharm. Bull. 1990, 38, 1601. (g) Borer, B. C.; Balogh, D. W. Tetrahedron Lett. 1991, 32, 1039. (h) Georg, G. I.; Akgün, E.; Mashava, P.; Milstead, M.; He, P.; Wu, Z.; Velde, D. V.; Takusagawa, F. Tetrahedron Lett. 1992, 33, 2111. (i) Georg, G. I.; Mashava, P. M.; Guan, X. Tetrahedron Lett. 1991, 32, 581. (j) Gunda, T. E.; Vieth, S.; Kover, K. E.; Sztaricskkai, F. Tetrahedron Lett. 1990, 31, 6707.
79. For significant examples, see: (a) Dugat, D.; Just, G.; Sahoo, S. Can. J. Chem. 1987, 65, 88. (b) Zamboni, R.; Just, G. Can. J. Chem. 1979, 57, 1945. (c) Kronenthal, D. R., Han, C. Y.; Taylor, M. K. J. Org. Chem. 1982, 47, 2765. (d) Evans, D. E.; Sjogren, E. B. Tetrahedron Lett. 1985, 26, 3783. (e) Ikota, N.; Hanaki, A. Heterocycles 1984, 22, 2227. (f) Ikota, N. Chem. Pharm. Bull. 1990, 38, 1601. (g) Borer, B. C.; Balogh, D. W. Tetrahedron Lett. 1991, 32, 1039. (h) Georg, G. I.; Akgün, E.; Mashava, P.; Milstead, M.; He, P.; Wu, Z.; Velde, D. V.; Takusagawa, F. Tetrahedron Lett. 1992, 33, 2111. (i) Georg, G. I.; Mashava, P. M.; Guan, X. Tetrahedron Lett. 1991, 32, 581. (j) Gunda, T. E.; Vieth, S.; Kover, K. E.; Sztaricskkai, F. Tetrahedron Lett. 1990, 31, 6707.
80. For significant examples, see: (a) Dugat, D.; Just, G.; Sahoo, S. Can. J. Chem. 1987, 65, 88. (b) Zamboni, R.; Just, G. Can. J. Chem. 1979, 57, 1945. (c) Kronenthal, D. R., Han, C. Y.; Taylor, M. K. J. Org. Chem. 1982, 47, 2765. (d) Evans, D. E.; Sjogren, E. B. Tetrahedron Lett. 1985, 26, 3783. (e) Ikota, N.; Hanaki, A. Heterocycles 1984, 22, 2227. (f) Ikota, N. Chem. Pharm. Bull. 1990, 38, 1601. (g) Borer, B. C.; Balogh, D. W. Tetrahedron Lett. 1991, 32, 1039. (h) Georg, G. I.; Akgün, E.; Mashava, P.; Milstead, M.; He, P.; Wu, Z.; Velde, D. V.; Takusagawa, F. Tetrahedron Lett. 1992, 33, 2111. (i) Georg, G. I.; Mashava, P. M.; Guan, X. Tetrahedron Lett. 1991, 32, 581. (j) Gunda, T. E.; Vieth, S.; Kover, K. E.; Sztaricskkai, F. Tetrahedron Lett. 1990, 31, 6707.
81. For significant examples, see: (a) Dugat, D.; Just, G.; Sahoo, S. Can. J. Chem. 1987, 65, 88. (b) Zamboni, R.; Just, G. Can. J. Chem. 1979, 57, 1945. (c) Kronenthal, D. R., Han, C. Y.; Taylor, M. K. J. Org. Chem. 1982, 47, 2765. (d) Evans, D. E.; Sjogren, E. B. Tetrahedron Lett. 1985, 26, 3783. (e) Ikota, N.; Hanaki, A. Heterocycles 1984, 22, 2227. (f) Ikota, N. Chem. Pharm. Bull. 1990, 38, 1601. (g) Borer, B. C.; Balogh, D. W. Tetrahedron Lett. 1991, 32, 1039. (h) Georg, G. I.; Akgün, E.; Mashava, P.; Milstead, M.; He, P.; Wu, Z.; Velde, D. V.; Takusagawa, F. Tetrahedron Lett. 1992, 33, 2111. (i) Georg, G. I.; Mashava, P. M.; Guan, X. Tetrahedron Lett. 1991, 32, 581. (j) Gunda, T. E.; Vieth, S.; Kover, K. E.; Sztaricskkai, F. Tetrahedron Lett. 1990, 31, 6707.
82. For significant examples, see: (a) Dugat, D.; Just, G.; Sahoo, S. Can. J. Chem. 1987, 65, 88. (b) Zamboni, R.; Just, G. Can. J. Chem. 1979, 57, 1945. (c) Kronenthal, D. R., Han, C. Y.; Taylor, M. K. J. Org. Chem. 1982, 47, 2765. (d) Evans, D. E.; Sjogren, E. B. Tetrahedron Lett. 1985, 26, 3783. (e) Ikota, N.; Hanaki, A. Heterocycles 1984, 22, 2227. (f) Ikota, N. Chem. Pharm. Bull. 1990, 38, 1601. (g) Borer, B. C.; Balogh, D. W. Tetrahedron Lett. 1991, 32, 1039. (h) Georg, G. I.; Akgün, E.; Mashava, P.; Milstead, M.; He, P.; Wu, Z.; Velde, D. V.; Takusagawa, F. Tetrahedron Lett. 1992, 33, 2111. (i) Georg, G. I.; Mashava, P. M.; Guan, X. Tetrahedron Lett. 1991, 32, 581. (j) Gunda, T. E.; Vieth, S.; Kover, K. E.; Sztaricskkai, F. Tetrahedron Lett. 1990, 31, 6707.
83. For significant examples, see: (a) Dugat, D.; Just, G.; Sahoo, S. Can. J. Chem. 1987, 65, 88. (b) Zamboni, R.; Just, G. Can. J. Chem. 1979, 57, 1945. (c) Kronenthal, D. R., Han, C. Y.; Taylor, M. K. J. Org. Chem. 1982, 47, 2765. (d) Evans, D. E.; Sjogren, E. B. Tetrahedron Lett. 1985, 26, 3783. (e) Ikota, N.; Hanaki, A. Heterocycles 1984, 22, 2227. (f) Ikota, N. Chem. Pharm. Bull. 1990, 38, 1601. (g) Borer, B. C.; Balogh, D. W. Tetrahedron Lett. 1991, 32, 1039. (h) Georg, G. I.; Akgün, E.; Mashava, P.; Milstead, M.; He, P.; Wu, Z.; Velde, D. V.; Takusagawa, F. Tetrahedron Lett. 1992, 33, 2111. (i) Georg, G. I.; Mashava, P. M.; Guan, X. Tetrahedron Lett. 1991, 32, 581. (j) Gunda, T. E.; Vieth, S.; Kover, K. E.; Sztaricskkai, F. Tetrahedron Lett. 1990, 31, 6707.
84. For significant examples, see: (a) Dugat, D.; Just, G.; Sahoo, S. Can. J. Chem. 1987, 65, 88. (b) Zamboni, R.; Just, G. Can. J. Chem. 1979, 57, 1945. (c) Kronenthal, D. R., Han, C. Y.; Taylor, M. K. J. Org. Chem. 1982, 47, 2765. (d) Evans, D. E.; Sjogren, E. B. Tetrahedron Lett. 1985, 26, 3783. (e) Ikota, N.; Hanaki, A. Heterocycles 1984, 22, 2227. (f) Ikota, N. Chem. Pharm. Bull. 1990, 38, 1601. (g) Borer, B. C.; Balogh, D. W. Tetrahedron Lett. 1991, 32, 1039. (h) Georg, G. I.; Akgün, E.; Mashava, P.; Milstead, M.; He, P.; Wu, Z.; Velde, D. V.; Takusagawa, F. Tetrahedron Lett. 1992, 33, 2111. (i) Georg, G. I.; Mashava, P. M.; Guan, X. Tetrahedron Lett. 1991, 32, 581. (j) Gunda, T. E.; Vieth, S.; Kover, K. E.; Sztaricskkai, F. Tetrahedron Lett. 1990, 31, 6707.
85. For significant examples, see: (a) Dugat, D.; Just, G.; Sahoo, S. Can. J. Chem. 1987, 65, 88. (b) Zamboni, R.; Just, G. Can. J. Chem. 1979, 57, 1945. (c) Kronenthal, D. R., Han, C. Y.; Taylor, M. K. J. Org. Chem. 1982, 47, 2765. (d) Evans, D. E.; Sjogren, E. B. Tetrahedron Lett. 1985, 26, 3783. (e) Ikota, N.; Hanaki, A. Heterocycles 1984, 22, 2227. (f) Ikota, N. Chem. Pharm. Bull. 1990, 38, 1601. (g) Borer, B. C.; Balogh, D. W. Tetrahedron Lett. 1991, 32, 1039. (h) Georg, G. I.; Akgün, E.; Mashava, P.; Milstead, M.; He, P.; Wu, Z.; Velde, D. V.; Takusagawa, F. Tetrahedron Lett. 1992, 33, 2111. (i) Georg, G. I.; Mashava, P. M.; Guan, X. Tetrahedron Lett. 1991, 32, 581. (j) Gunda, T. E.; Vieth, S.; Kover, K. E.; Sztaricskkai, F. Tetrahedron Lett. 1990, 31, 6707.
86. For significant examples, see: (a) Dugat, D.; Just, G.; Sahoo, S. Can. J. Chem. 1987, 65, 88. (b) Zamboni, R.; Just, G. Can. J. Chem. 1979, 57, 1945. (c) Kronenthal, D. R., Han, C. Y.; Taylor, M. K. J. Org. Chem. 1982, 47, 2765. (d) Evans, D. E.; Sjogren, E. B. Tetrahedron Lett. 1985, 26, 3783. (e) Ikota, N.; Hanaki, A. Heterocycles 1984, 22, 2227. (f) Ikota, N. Chem. Pharm. Bull. 1990, 38, 1601. (g) Borer, B. C.; Balogh, D. W. Tetrahedron Lett. 1991, 32, 1039. (h) Georg, G. I.; Akgün, E.; Mashava, P.; Milstead, M.; He, P.; Wu, Z.; Velde, D. V.; Takusagawa, F. Tetrahedron Lett. 1992, 33, 2111. (i) Georg, G. I.; Mashava, P. M.; Guan, X. Tetrahedron Lett. 1991, 32, 581. (j) Gunda, T. E.; Vieth, S.; Kover, K. E.; Sztaricskkai, F. Tetrahedron Lett. 1990, 31, 6707.
87. Katagiri, N.; Miura, R.; Niwa, R.; Kato, T. Chem. Pharm. Bull. 1983, 31, 538.
88. 1H-NMR of the crude reaction mixture before the usual acidic workup.
89. (a) Kirmse, W.; Rondan, N. G.; Houk, K. N. J. Am. Chem. Soc. 1984, 106, 1989.
90. (b) Houk, K. N.; Rondan, N. G. J. Am. Chem. Soc. 1985, 107, 2099.
91. (c) Rudolf, K.; Spellmeyer, D. C.; Houk, K. N. J. Org. Chem. 1987, 52, 3708.
92. (d) Houk, K. N.; Spellmeyer, D. C.; Jefford, Ch.W.; Rimbault, C. G.; Wang, Y.; Miller, R. D. J. Org. Chem. 1988, 53, 2125.
93. (e) Buda, A. B.; Wang, Y.; Houk, K. N. J. Org. Chem. 1989, 54, 2264.
94. (f) Jefford, Ch.W.; Bernardinelli, G.; Wang, Y.; Spellmeyer, D. C.; Buda, A.; Houk, K. N. J. Am. Chem. Soc. 1992, 114, 1157.
95. (g) Niwayama, S.; Houk, K. N. Tetrahedron Lett. 1993, 34, 1251.
96. (h) Nakamura, K. Houk, K. N. J. Org. Chem. 1995, 60, 686.
97. (a) Dewar, M. J. S.; Olivella, S.; Stewart, J. J. P. J. Am. Chem. Soc. 1986, 108, 5771.
98. (b) Dannenberg, J. J.; Tanaka, K. J. Am. Chem. Soc. 1985, 107, 671.
99. (c) Dewar, M. J. S.; Jie, C. J. Am. Chem. Soc. 1987, 109, 5893.
100. Schmidt, M. W.; Nguyen, K. A.; Gordon, M. S.; Montgomery, J. A. J. Am. Chem. Soc. 1991, 113, 5998.
101. In line with this result, the Mulliken Charges for the C(3) and C(4) atoms are higher at the HF/3-21G level than at the CASSCF-(2,2)/3-21G level. Similarly, the dipole moments of TSβa at the HF/ 3-21G and CASSCF/3-21G levels are 2.466 and 1.470 D, respectively.
102. Evanseck, J. D.; Thomas IV, B. E.; Spellmeyer, D. C.; Houk, K. N. J. Org. Chem. 1995, 60, 7134.
103. R parameters for chlorine and methyl are -0.21 and -0.10, respectively. Therefore, the resonance terms, more relevant in this case, suggest that chlorine is a better donor than methyl if inductive effects are not considered. See: Isaacs, N. L. Physical Organic Chemistry; Longman: Essex, 1987; p 158 and references therein.
104. For a high-level computational treatment of this problem, see: Kozlowski, P.M.; Dupuis, M.; Davidson, E. R. J. Am. Chem. Soc. 1995, 117, 774.
105. Perrin, D. D.; Armarego, W. L. F. Purification of Laboratory Chemicals; Pergamon: Oxford, 1988.
106. The author has deposited atomic coordinates for 6 with the Cambridge Crystallographic Data Centre. The coordinates can be obtained, on request, from the Director, Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge, CB2 1EZ, UK.