Single crystal X-ray analyses of a series of hexamethylphosphoramide-coordinated complexes of rare earth triflates: Existence of tetrad effects in the coordinate bonds

Chemistry Letters

Volumn , Issue 10, 1996, Pages 875-876

  Imamoto, Tsuneo ^a   Nishiura, Masayoshi ^a   Yamanoi, Yoshinori ^a   Tsuruta, Hideyuki ^a   Yamaguchi, Kentaro ^a  

^a CHIBA UNIVERSITY   (Japan)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0030375347     PISSN: 03667022     EISSN: None     Source Type: Journal    
DOI: 10.1246/cl.1996.875     Document Type: Article

References (39)

1. For representative reviews, see the following: H. B. Kagan, Tetrahedron, 42, 6573 (1986); G. A. Molander, In "Comprehensive Organic Synthesis," ed by B. M. Trost, Pergamon, Oxford (1991), Vol. 1, p. 251; T. Imamoto, In "Comprehensive Organic Synthesis," ed by B. M. Trost, Pergamon, Oxford (1991), Vol. 1, p. 231; G. A. Molander, Chem. Rev., 92, 29 (1992); T. Imamoto, "Lanthanides in Organic Synthesis," ed by A. R. Katritzky, O. Meth-Cohn, and C. W. Rees, Academic Press, London (1994).
2. For representative reviews, see the following: H. B. Kagan, Tetrahedron, 42, 6573 (1986); G. A. Molander, In "Comprehensive Organic Synthesis," ed by B. M. Trost, Pergamon, Oxford (1991), Vol. 1, p. 251; T. Imamoto, In "Comprehensive Organic Synthesis," ed by B. M. Trost, Pergamon, Oxford (1991), Vol. 1, p. 231; G. A. Molander, Chem. Rev., 92, 29 (1992); T. Imamoto, "Lanthanides in Organic Synthesis," ed by A. R. Katritzky, O. Meth-Cohn, and C. W. Rees, Academic Press, London (1994).
3. For representative reviews, see the following: H. B. Kagan, Tetrahedron, 42, 6573 (1986); G. A. Molander, In "Comprehensive Organic Synthesis," ed by B. M. Trost, Pergamon, Oxford (1991), Vol. 1, p. 251; T. Imamoto, In "Comprehensive Organic Synthesis," ed by B. M. Trost, Pergamon, Oxford (1991), Vol. 1, p. 231; G. A. Molander, Chem. Rev., 92, 29 (1992); T. Imamoto, "Lanthanides in Organic Synthesis," ed by A. R. Katritzky, O. Meth-Cohn, and C. W. Rees, Academic Press, London (1994).
4. For representative reviews, see the following: H. B. Kagan, Tetrahedron, 42, 6573 (1986); G. A. Molander, In "Comprehensive Organic Synthesis," ed by B. M. Trost, Pergamon, Oxford (1991), Vol. 1, p. 251; T. Imamoto, In "Comprehensive Organic Synthesis," ed by B. M. Trost, Pergamon, Oxford (1991), Vol. 1, p. 231; G. A. Molander, Chem. Rev., 92, 29 (1992); T. Imamoto, "Lanthanides in Organic Synthesis," ed by A. R. Katritzky, O. Meth-Cohn, and C. W. Rees, Academic Press, London (1994).
5. For representative reviews, see the following: H. B. Kagan, Tetrahedron, 42, 6573 (1986); G. A. Molander, In "Comprehensive Organic Synthesis," ed by B. M. Trost, Pergamon, Oxford (1991), Vol. 1, p. 251; T. Imamoto, In "Comprehensive Organic Synthesis," ed by B. M. Trost, Pergamon, Oxford (1991), Vol. 1, p. 231; G. A. Molander, Chem. Rev., 92, 29 (1992); T. Imamoto, "Lanthanides in Organic Synthesis," ed by A. R. Katritzky, O. Meth-Cohn, and C. W. Rees, Academic Press, London (1994).
6. Recent representative examples of the use of rare earth complexes in stereoselective organic transformations: H. Sasai, T. Suzuki, S. Arai, T. Arai, and M. Shibasaki, J. Am. Chem. Soc., 114, 4418 (1992); H. Yasuda, H. Yamamoto, K. Yokota, S. Miyake, and A. Nakamura, J. Am. Chem. Soc., 114, 9080 (1992); D. A. Evans, S. G. Nelson, M. R. Gagné, and A. R. Muci, J. Am. Chem. Soc., 115, 9800 (1993); W. J. Evans, S. L. Gonzales, and J. W. Ziller, J. Am. Chem. Soc., 116, 2600 (1994); P. J. Shapiro, W. D. Cotter, W. P. Schaefer, J. A. Labinger, and J. E. Bercaw, J. Am. Chem. Soc., 116, 4623 (1994); M. A Giardello, V. P. Conticello, L. Brard, M. R. Gagné, and T. J. Marks, J. Am. Chem. Soc., 116, 10241 (1994); M. A. Giardello, Y. Yamamoto, L. Brard, and T. J. Marks, J. Am. Chem. Soc., 117, 3276 (1995); G. A. Molander and C. R. Harris, J. Am. Chem. Soc., 117, 3705 (1995); G. A. Molander and P. J. Nichols, J. Am. Chem. Soc., 117, 4415 (1995); P.-F. Fu, L. Brard, Y. Li, and T. J. Marks, J. Am. Chem. Soc., 117, 7157 (1995).
7. Recent representative examples of the use of rare earth complexes in stereoselective organic transformations: H. Sasai, T. Suzuki, S. Arai, T. Arai, and M. Shibasaki, J. Am. Chem. Soc., 114, 4418 (1992); H. Yasuda, H. Yamamoto, K. Yokota, S. Miyake, and A. Nakamura, J. Am. Chem. Soc., 114, 9080 (1992); D. A. Evans, S. G. Nelson, M. R. Gagné, and A. R. Muci, J. Am. Chem. Soc., 115, 9800 (1993); W. J. Evans, S. L. Gonzales, and J. W. Ziller, J. Am. Chem. Soc., 116, 2600 (1994); P. J. Shapiro, W. D. Cotter, W. P. Schaefer, J. A. Labinger, and J. E. Bercaw, J. Am. Chem. Soc., 116, 4623 (1994); M. A Giardello, V. P. Conticello, L. Brard, M. R. Gagné, and T. J. Marks, J. Am. Chem. Soc., 116, 10241 (1994); M. A. Giardello, Y. Yamamoto, L. Brard, and T. J. Marks, J. Am. Chem. Soc., 117, 3276 (1995); G. A. Molander and C. R. Harris, J. Am. Chem. Soc., 117, 3705 (1995); G. A. Molander and P. J. Nichols, J. Am. Chem. Soc., 117, 4415 (1995); P.-F. Fu, L. Brard, Y. Li, and T. J. Marks, J. Am. Chem. Soc., 117, 7157 (1995).
8. Recent representative examples of the use of rare earth complexes in stereoselective organic transformations: H. Sasai, T. Suzuki, S. Arai, T. Arai, and M. Shibasaki, J. Am. Chem. Soc., 114, 4418 (1992); H. Yasuda, H. Yamamoto, K. Yokota, S. Miyake, and A. Nakamura, J. Am. Chem. Soc., 114, 9080 (1992); D. A. Evans, S. G. Nelson, M. R. Gagné, and A. R. Muci, J. Am. Chem. Soc., 115, 9800 (1993); W. J. Evans, S. L. Gonzales, and J. W. Ziller, J. Am. Chem. Soc., 116, 2600 (1994); P. J. Shapiro, W. D. Cotter, W. P. Schaefer, J. A. Labinger, and J. E. Bercaw, J. Am. Chem. Soc., 116, 4623 (1994); M. A Giardello, V. P. Conticello, L. Brard, M. R. Gagné, and T. J. Marks, J. Am. Chem. Soc., 116, 10241 (1994); M. A. Giardello, Y. Yamamoto, L. Brard, and T. J. Marks, J. Am. Chem. Soc., 117, 3276 (1995); G. A. Molander and C. R. Harris, J. Am. Chem. Soc., 117, 3705 (1995); G. A. Molander and P. J. Nichols, J. Am. Chem. Soc., 117, 4415 (1995); P.-F. Fu, L. Brard, Y. Li, and T. J. Marks, J. Am. Chem. Soc., 117, 7157 (1995).
9. Recent representative examples of the use of rare earth complexes in stereoselective organic transformations: H. Sasai, T. Suzuki, S. Arai, T. Arai, and M. Shibasaki, J. Am. Chem. Soc., 114, 4418 (1992); H. Yasuda, H. Yamamoto, K. Yokota, S. Miyake, and A. Nakamura, J. Am. Chem. Soc., 114, 9080 (1992); D. A. Evans, S. G. Nelson, M. R. Gagné, and A. R. Muci, J. Am. Chem. Soc., 115, 9800 (1993); W. J. Evans, S. L. Gonzales, and J. W. Ziller, J. Am. Chem. Soc., 116, 2600 (1994); P. J. Shapiro, W. D. Cotter, W. P. Schaefer, J. A. Labinger, and J. E. Bercaw, J. Am. Chem. Soc., 116, 4623 (1994); M. A Giardello, V. P. Conticello, L. Brard, M. R. Gagné, and T. J. Marks, J. Am. Chem. Soc., 116, 10241 (1994); M. A. Giardello, Y. Yamamoto, L. Brard, and T. J. Marks, J. Am. Chem. Soc., 117, 3276 (1995); G. A. Molander and C. R. Harris, J. Am. Chem. Soc., 117, 3705 (1995); G. A. Molander and P. J. Nichols, J. Am. Chem. Soc., 117, 4415 (1995); P.-F. Fu, L. Brard, Y. Li, and T. J. Marks, J. Am. Chem. Soc., 117, 7157 (1995).
10. Recent representative examples of the use of rare earth complexes in stereoselective organic transformations: H. Sasai, T. Suzuki, S. Arai, T. Arai, and M. Shibasaki, J. Am. Chem. Soc., 114, 4418 (1992); H. Yasuda, H. Yamamoto, K. Yokota, S. Miyake, and A. Nakamura, J. Am. Chem. Soc., 114, 9080 (1992); D. A. Evans, S. G. Nelson, M. R. Gagné, and A. R. Muci, J. Am. Chem. Soc., 115, 9800 (1993); W. J. Evans, S. L. Gonzales, and J. W. Ziller, J. Am. Chem. Soc., 116, 2600 (1994); P. J. Shapiro, W. D. Cotter, W. P. Schaefer, J. A. Labinger, and J. E. Bercaw, J. Am. Chem. Soc., 116, 4623 (1994); M. A Giardello, V. P. Conticello, L. Brard, M. R. Gagné, and T. J. Marks, J. Am. Chem. Soc., 116, 10241 (1994); M. A. Giardello, Y. Yamamoto, L. Brard, and T. J. Marks, J. Am. Chem. Soc., 117, 3276 (1995); G. A. Molander and C. R. Harris, J. Am. Chem. Soc., 117, 3705 (1995); G. A. Molander and P. J. Nichols, J. Am. Chem. Soc., 117, 4415 (1995); P.-F. Fu, L. Brard, Y. Li, and T. J. Marks, J. Am. Chem. Soc., 117, 7157 (1995).
11. Recent representative examples of the use of rare earth complexes in stereoselective organic transformations: H. Sasai, T. Suzuki, S. Arai, T. Arai, and M. Shibasaki, J. Am. Chem. Soc., 114, 4418 (1992); H. Yasuda, H. Yamamoto, K. Yokota, S. Miyake, and A. Nakamura, J. Am. Chem. Soc., 114, 9080 (1992); D. A. Evans, S. G. Nelson, M. R. Gagné, and A. R. Muci, J. Am. Chem. Soc., 115, 9800 (1993); W. J. Evans, S. L. Gonzales, and J. W. Ziller, J. Am. Chem. Soc., 116, 2600 (1994); P. J. Shapiro, W. D. Cotter, W. P. Schaefer, J. A. Labinger, and J. E. Bercaw, J. Am. Chem. Soc., 116, 4623 (1994); M. A Giardello, V. P. Conticello, L. Brard, M. R. Gagné, and T. J. Marks, J. Am. Chem. Soc., 116, 10241 (1994); M. A. Giardello, Y. Yamamoto, L. Brard, and T. J. Marks, J. Am. Chem. Soc., 117, 3276 (1995); G. A. Molander and C. R. Harris, J. Am. Chem. Soc., 117, 3705 (1995); G. A. Molander and P. J. Nichols, J. Am. Chem. Soc., 117, 4415 (1995); P.-F. Fu, L. Brard, Y. Li, and T. J. Marks, J. Am. Chem. Soc., 117, 7157 (1995).
12. Recent representative examples of the use of rare earth complexes in stereoselective organic transformations: H. Sasai, T. Suzuki, S. Arai, T. Arai, and M. Shibasaki, J. Am. Chem. Soc., 114, 4418 (1992); H. Yasuda, H. Yamamoto, K. Yokota, S. Miyake, and A. Nakamura, J. Am. Chem. Soc., 114, 9080 (1992); D. A. Evans, S. G. Nelson, M. R. Gagné, and A. R. Muci, J. Am. Chem. Soc., 115, 9800 (1993); W. J. Evans, S. L. Gonzales, and J. W. Ziller, J. Am. Chem. Soc., 116, 2600 (1994); P. J. Shapiro, W. D. Cotter, W. P. Schaefer, J. A. Labinger, and J. E. Bercaw, J. Am. Chem. Soc., 116, 4623 (1994); M. A Giardello, V. P. Conticello, L. Brard, M. R. Gagné, and T. J. Marks, J. Am. Chem. Soc., 116, 10241 (1994); M. A. Giardello, Y. Yamamoto, L. Brard, and T. J. Marks, J. Am. Chem. Soc., 117, 3276 (1995); G. A. Molander and C. R. Harris, J. Am. Chem. Soc., 117, 3705 (1995); G. A. Molander and P. J. Nichols, J. Am. Chem. Soc., 117, 4415 (1995); P.-F. Fu, L. Brard, Y. Li, and T. J. Marks, J. Am. Chem. Soc., 117, 7157 (1995).
13. Recent representative examples of the use of rare earth complexes in stereoselective organic transformations: H. Sasai, T. Suzuki, S. Arai, T. Arai, and M. Shibasaki, J. Am. Chem. Soc., 114, 4418 (1992); H. Yasuda, H. Yamamoto, K. Yokota, S. Miyake, and A. Nakamura, J. Am. Chem. Soc., 114, 9080 (1992); D. A. Evans, S. G. Nelson, M. R. Gagné, and A. R. Muci, J. Am. Chem. Soc., 115, 9800 (1993); W. J. Evans, S. L. Gonzales, and J. W. Ziller, J. Am. Chem. Soc., 116, 2600 (1994); P. J. Shapiro, W. D. Cotter, W. P. Schaefer, J. A. Labinger, and J. E. Bercaw, J. Am. Chem. Soc., 116, 4623 (1994); M. A Giardello, V. P. Conticello, L. Brard, M. R. Gagné, and T. J. Marks, J. Am. Chem. Soc., 116, 10241 (1994); M. A. Giardello, Y. Yamamoto, L. Brard, and T. J. Marks, J. Am. Chem. Soc., 117, 3276 (1995); G. A. Molander and C. R. Harris, J. Am. Chem. Soc., 117, 3705 (1995); G. A. Molander and P. J. Nichols, J. Am. Chem. Soc., 117, 4415 (1995); P.-F. Fu, L. Brard, Y. Li, and T. J. Marks, J. Am. Chem. Soc., 117, 7157 (1995).
14. Recent representative examples of the use of rare earth complexes in stereoselective organic transformations: H. Sasai, T. Suzuki, S. Arai, T. Arai, and M. Shibasaki, J. Am. Chem. Soc., 114, 4418 (1992); H. Yasuda, H. Yamamoto, K. Yokota, S. Miyake, and A. Nakamura, J. Am. Chem. Soc., 114, 9080 (1992); D. A. Evans, S. G. Nelson, M. R. Gagné, and A. R. Muci, J. Am. Chem. Soc., 115, 9800 (1993); W. J. Evans, S. L. Gonzales, and J. W. Ziller, J. Am. Chem. Soc., 116, 2600 (1994); P. J. Shapiro, W. D. Cotter, W. P. Schaefer, J. A. Labinger, and J. E. Bercaw, J. Am. Chem. Soc., 116, 4623 (1994); M. A Giardello, V. P. Conticello, L. Brard, M. R. Gagné, and T. J. Marks, J. Am. Chem. Soc., 116, 10241 (1994); M. A. Giardello, Y. Yamamoto, L. Brard, and T. J. Marks, J. Am. Chem. Soc., 117, 3276 (1995); G. A. Molander and C. R. Harris, J. Am. Chem. Soc., 117, 3705 (1995); G. A. Molander and P. J. Nichols, J. Am. Chem. Soc., 117, 4415 (1995); P.-F. Fu, L. Brard, Y. Li, and T. J. Marks, J. Am. Chem. Soc., 117, 7157 (1995).
15. Recent representative examples of the use of rare earth complexes in stereoselective organic transformations: H. Sasai, T. Suzuki, S. Arai, T. Arai, and M. Shibasaki, J. Am. Chem. Soc., 114, 4418 (1992); H. Yasuda, H. Yamamoto, K. Yokota, S. Miyake, and A. Nakamura, J. Am. Chem. Soc., 114, 9080 (1992); D. A. Evans, S. G. Nelson, M. R. Gagné, and A. R. Muci, J. Am. Chem. Soc., 115, 9800 (1993); W. J. Evans, S. L. Gonzales, and J. W. Ziller, J. Am. Chem. Soc., 116, 2600 (1994); P. J. Shapiro, W. D. Cotter, W. P. Schaefer, J. A. Labinger, and J. E. Bercaw, J. Am. Chem. Soc., 116, 4623 (1994); M. A Giardello, V. P. Conticello, L. Brard, M. R. Gagné, and T. J. Marks, J. Am. Chem. Soc., 116, 10241 (1994); M. A. Giardello, Y. Yamamoto, L. Brard, and T. J. Marks, J. Am. Chem. Soc., 117, 3276 (1995); G. A. Molander and C. R. Harris, J. Am. Chem. Soc., 117, 3705 (1995); G. A. Molander and P. J. Nichols, J. Am. Chem. Soc., 117, 4415 (1995); P.-F. Fu, L. Brard, Y. Li, and T. J. Marks, J. Am. Chem. Soc., 117, 7157 (1995).
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18. w = 0.072. Details of the all molecular structures have been deposited at the Cambridge Crystallographic Centre.
19. The atomic distances (3.17-3.44 Å) between the chloroform carbon and the oxygen atoms of the Inflate anion indicate that the hydrogen atom of chloroform interacts with the two oxygen atoms of the triflate anion.
20. The mean values of four M-O(HMPA) bonds and two M-O(OTf) bonds also exhibit similar tetrad effects, respectively.
21. D. F. Peppard, G. W. Mason, and S. Lewey, J. Inorg. Nucl. Chem., 31, 2271 (1960); D. F. Peppard, C. A. A. Bloomquist, E. P. Horwitz, S. Lewey, and G. W. Mason, J. Inorg. Nucl. Chem., 32, 339 (1970); S. Siekierski, J. Inorg. Nucl. Chem., 32, 519 (1970).
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23. D. F. Peppard, G. W. Mason, and S. Lewey, J. Inorg. Nucl. Chem., 31, 2271 (1960); D. F. Peppard, C. A. A. Bloomquist, E. P. Horwitz, S. Lewey, and G. W. Mason, J. Inorg. Nucl. Chem., 32, 339 (1970); S. Siekierski, J. Inorg. Nucl. Chem., 32, 519 (1970).
24. L. J. Nugent, J. Inorg. Nucl. Chem., 32, 3485 (1970).
25. S. P. Sinha, In "Systematics and the Properties of the Lanthanides," ed by S. P. Sinha, Reidel, Dordrecht (1983), p. 71.
26. Mean values (Å) of four P-O bond lenghts: Sc 1.503; Y 1.495; La 1.482; Ce 1.485; Pr 1.491; Nd 1.488; Sm 1.486; Eu 1.490; Gd 1.491; Tb 1.491; Dy 1.493; Ho 1.490; Er 1.497; Tm 1.496; Yb 1.505; Lu 1.489. Standard deviations of P-O bond lengths ranged in 0.003-0.006 Å.
27. 14), renders the ytterbium(III) ion more electron-attracting in all lanthanide(III) ions.
28. K. Takaki, K. Nagase, F. Beppu, and Y. Fujiwara, Chem. Lett., 1991, 1665; A. Kawada, S, Mitamura, and S. Kobayashi, J. Chem. Soc., Chem. Commun., 1993, 1157; S. Kobayashi, Synlett, 1994, 689; S. Kobayashi and H. Ishitani, J. Am. Chem. Soc., 116, 4083 (1994); S. Kobayashi and I. Hachiya, J. Org. Chem., 59, 3590 (1994).
29. K. Takaki, K. Nagase, F. Beppu, and Y. Fujiwara, Chem. Lett., 1991, 1665; A. Kawada, S, Mitamura, and S. Kobayashi, J. Chem. Soc., Chem. Commun., 1993, 1157; S. Kobayashi, Synlett, 1994, 689; S. Kobayashi and H. Ishitani, J. Am. Chem. Soc., 116, 4083 (1994); S. Kobayashi and I. Hachiya, J. Org. Chem., 59, 3590 (1994).
30. K. Takaki, K. Nagase, F. Beppu, and Y. Fujiwara, Chem. Lett., 1991, 1665; A. Kawada, S, Mitamura, and S. Kobayashi, J. Chem. Soc., Chem. Commun., 1993, 1157; S. Kobayashi, Synlett, 1994, 689; S. Kobayashi and H. Ishitani, J. Am. Chem. Soc., 116, 4083 (1994); S. Kobayashi and I. Hachiya, J. Org. Chem., 59, 3590 (1994).
31. K. Takaki, K. Nagase, F. Beppu, and Y. Fujiwara, Chem. Lett., 1991, 1665; A. Kawada, S, Mitamura, and S. Kobayashi, J. Chem. Soc., Chem. Commun., 1993, 1157; S. Kobayashi, Synlett, 1994, 689; S. Kobayashi and H. Ishitani, J. Am. Chem. Soc., 116, 4083 (1994); S. Kobayashi and I. Hachiya, J. Org. Chem., 59, 3590 (1994).
32. K. Takaki, K. Nagase, F. Beppu, and Y. Fujiwara, Chem. Lett., 1991, 1665; A. Kawada, S, Mitamura, and S. Kobayashi, J. Chem. Soc., Chem. Commun., 1993, 1157; S. Kobayashi, Synlett, 1994, 689; S. Kobayashi and H. Ishitani, J. Am. Chem. Soc., 116, 4083 (1994); S. Kobayashi and I. Hachiya, J. Org. Chem., 59, 3590 (1994).
33. 3 in organic syntheses, see the following: G. A. Molander, E. R. Burkhardt, and P. Weinig, J. Org. Chem., 55, 4990 (1990); S. Kobayashi and I. Hachiya, Tetrahedron Lett., 33, 1625 (1992); J. Inanaga, Y. Yokoyama, and T. Hanamoto, Tetrahedron Lett., 34, 2791 (1993); I. Hachiya and S. Kobayashi, J. Org. Chem., 58, 6958 (1993); W. J. Sanders and L. L. Kiessling, Tetrahedron Lett., 35, 7335 (1994); M. Meguro, N. Asao, and Y. Yamamoto, J. Chem. Soc., Perkin Trans, 1, 2597 (1994); K. Ishihara, M. Kubota, H. Kurihara, and H. Yamamoto, J. Am. Chem. Soc., 117, 4413 (1995).
34. 3 in organic syntheses, see the following: G. A. Molander, E. R. Burkhardt, and P. Weinig, J. Org. Chem., 55, 4990 (1990); S. Kobayashi and I. Hachiya, Tetrahedron Lett., 33, 1625 (1992); J. Inanaga, Y. Yokoyama, and T. Hanamoto, Tetrahedron Lett., 34, 2791 (1993); I. Hachiya and S. Kobayashi, J. Org. Chem., 58, 6958 (1993); W. J. Sanders and L. L. Kiessling, Tetrahedron Lett., 35, 7335 (1994); M. Meguro, N. Asao, and Y. Yamamoto, J. Chem. Soc., Perkin Trans, 1, 2597 (1994); K. Ishihara, M. Kubota, H. Kurihara, and H. Yamamoto, J. Am. Chem. Soc., 117, 4413 (1995).
35. 3 in organic syntheses, see the following: G. A. Molander, E. R. Burkhardt, and P. Weinig, J. Org. Chem., 55, 4990 (1990); S. Kobayashi and I. Hachiya, Tetrahedron Lett., 33, 1625 (1992); J. Inanaga, Y. Yokoyama, and T. Hanamoto, Tetrahedron Lett., 34, 2791 (1993); I. Hachiya and S. Kobayashi, J. Org. Chem., 58, 6958 (1993); W. J. Sanders and L. L. Kiessling, Tetrahedron Lett., 35, 7335 (1994); M. Meguro, N. Asao, and Y. Yamamoto, J. Chem. Soc., Perkin Trans, 1, 2597 (1994); K. Ishihara, M. Kubota, H. Kurihara, and H. Yamamoto, J. Am. Chem. Soc., 117, 4413 (1995).
36. 3 in organic syntheses, see the following: G. A. Molander, E. R. Burkhardt, and P. Weinig, J. Org. Chem., 55, 4990 (1990); S. Kobayashi and I. Hachiya, Tetrahedron Lett., 33, 1625 (1992); J. Inanaga, Y. Yokoyama, and T. Hanamoto, Tetrahedron Lett., 34, 2791 (1993); I. Hachiya and S. Kobayashi, J. Org. Chem., 58, 6958 (1993); W. J. Sanders and L. L. Kiessling, Tetrahedron Lett., 35, 7335 (1994); M. Meguro, N. Asao, and Y. Yamamoto, J. Chem. Soc., Perkin Trans, 1, 2597 (1994); K. Ishihara, M. Kubota, H. Kurihara, and H. Yamamoto, J. Am. Chem. Soc., 117, 4413 (1995).
37. 3 in organic syntheses, see the following: G. A. Molander, E. R. Burkhardt, and P. Weinig, J. Org. Chem., 55, 4990 (1990); S. Kobayashi and I. Hachiya, Tetrahedron Lett., 33, 1625 (1992); J. Inanaga, Y. Yokoyama, and T. Hanamoto, Tetrahedron Lett., 34, 2791 (1993); I. Hachiya and S. Kobayashi, J. Org. Chem., 58, 6958 (1993); W. J. Sanders and L. L. Kiessling, Tetrahedron Lett., 35, 7335 (1994); M. Meguro, N. Asao, and Y. Yamamoto, J. Chem. Soc., Perkin Trans, 1, 2597 (1994); K. Ishihara, M. Kubota, H. Kurihara, and H. Yamamoto, J. Am. Chem. Soc., 117, 4413 (1995).
38. 3 in organic syntheses, see the following: G. A. Molander, E. R. Burkhardt, and P. Weinig, J. Org. Chem., 55, 4990 (1990); S. Kobayashi and I. Hachiya, Tetrahedron Lett., 33, 1625 (1992); J. Inanaga, Y. Yokoyama, and T. Hanamoto, Tetrahedron Lett., 34, 2791 (1993); I. Hachiya and S. Kobayashi, J. Org. Chem., 58, 6958 (1993); W. J. Sanders and L. L. Kiessling, Tetrahedron Lett., 35, 7335 (1994); M. Meguro, N. Asao, and Y. Yamamoto, J. Chem. Soc., Perkin Trans, 1, 2597 (1994); K. Ishihara, M. Kubota, H. Kurihara, and H. Yamamoto, J. Am. Chem. Soc., 117, 4413 (1995).
39. 3 in organic syntheses, see the following: G. A. Molander, E. R. Burkhardt, and P. Weinig, J. Org. Chem., 55, 4990 (1990); S. Kobayashi and I. Hachiya, Tetrahedron Lett., 33, 1625 (1992); J. Inanaga, Y. Yokoyama, and T. Hanamoto, Tetrahedron Lett., 34, 2791 (1993); I. Hachiya and S. Kobayashi, J. Org. Chem., 58, 6958 (1993); W. J. Sanders and L. L. Kiessling, Tetrahedron Lett., 35, 7335 (1994); M. Meguro, N. Asao, and Y. Yamamoto, J. Chem. Soc., Perkin Trans, 1, 2597 (1994); K. Ishihara, M. Kubota, H. Kurihara, and H. Yamamoto, J. Am. Chem. Soc., 117, 4413 (1995).