Cyclization of enantio-enriched α-(Homoallyloxy)alkyllithiums: Evidence for retention of configuration at the carbanion center

Tetrahedron Letters

Volumn 38, Issue 52, 1997, Pages 8939-8942

  Tomooka, Katsuhiko ^a   Komine, Nobuyuki ^a   Nakai, Takeshi ^a  

^a TOKYO INSTITUTE OF TECHNOLOGY   (Japan)

Author keywords

[No Author keywords available]

Indexed keywords

LITHIUM;

ARTICLE; CONTROLLED STUDY; CYCLIZATION; DIASTEREOISOMER; DRUG SYNTHESIS; ENANTIOMER;

EID: 0030816980     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4039(97)10327-6     Document Type: Article

References (18)

1. Still, W.C.; Sreekumear, C. J. Am. Chem. Soc. 1980, 102, 1201-1202. Sawyer, J. S.; Kucerovy, A.; Macdonald, T. L.; McGarvey, G. L. J. Am. Chem. Soc. 1988, 110, 842-853.
2. Still, W.C.; Sreekumear, C. J. Am. Chem. Soc. 1980, 102, 1201-1202. Sawyer, J. S.; Kucerovy, A.; Macdonald, T. L.; McGarvey, G. L. J. Am. Chem. Soc. 1988, 110, 842-853.
3. Review: Tomooka, K.; Igarashi, T.; Komine, N.; Nakai, T. J. Synth. Org. Chem., Jpn. 1995, 53, 480-486.
4. a) Tomooka, K.; Igarashi, T.; Watanabe, M.; Nakai,T. Tetrahedron Lett. 1992, 33, 5795-5799;
5. b) Tomooka, K.; Komine, N.; Nakai, T. Synlett 1997, in press;
6. c) [1,2]-Wittig rearrangement: Tomooka, K.; Igarashi, T.; Nakai, T. Tetrahedron 1994, 50, 5927-5932.
7. a) Bailey, W. F.; Patricia, J. J.; DelGobbo, V. C.; Jarret, R. M.; Okarma, P. J. J. Org. Chem. 1985, 50, 1999-2000.
8. b) Reviews on carbanion cyclization: Bailey, W.F.; Ovaska, T. V. In Advances in Detailed Reaction Mechanisms, Vol. 3, 1994, 251-273. Knochel, P. In Comprehensive Organic Synthesis, Vol. 4; Trost, B. M.; Fleming, I., Ed.; Pergamon: New York, 1991; p 871-872.
9. b) Reviews on carbanion cyclization: Bailey, W.F.; Ovaska, T. V. In Advances in Detailed Reaction Mechanisms, Vol. 3, 1994, 251-273. Knochel, P. In Comprehensive Organic Synthesis, Vol. 4; Trost, B. M.; Fleming, I., Ed.; Pergamon: New York, 1991; p 871-872.
10. For similar cyclizations of α-(homoallyloxy)alkyllithiums (racemic) generated from α-(phenylthio)ether via the reductive lithiation method: Broka, C. A.; Shen, T. J. Am. Chem. Soc. 1989, 111, 2981-2984.
11. Bailey, W.F.; Khanolkar, A. D.; Gavaskar, K.; Ovaska, T. V.; Rossi, K.; Thiel, Y.; Wiberg, K. B. J. Am. Chem. Soc. 1991, 113, 5720-5727.
12. A part of this work was presented at the Annual Meeting of the Chemical Society of Japan, March, 1994, Abstr. 1K114. More recently, Coldham et al. have reported that the cyclization of an aza analog proceeds with retention of configuration at the carbanion center: Coldham, I.; Hufton, R.; Snowden, D. J. J. Am. Chem. Soc. 1996, 118, 5322-5323.
13. 2). formula presented
14. 3; (2S,3R)-isomer, 95% ee).
15. The reason why such a large excess of n-BuLi is required is not clear at present. However, it might be considered that the excess n-BuLi coordinates with the ether oxygen, thereby making it possible for the counter lithium which initially coordinates with the adjacent oxygen to interact with the olefinic bond.
16. Broka et al have also reported the anionic cyclization of α-(homoallyloxy)alkyllithiums which involves the concomitant expulsion of an alkoxide provide a high steroselecti vity and an improved chemical yield; Broka, C. A.; Lee, W. J.; Shen, T. J. Org. Chem. 1988, 53, 1336-1338, and ref 5 .
17. The enantio-enriched (S)-stannyl alcohol was prepared by the literature method: Tomooka, K.; Igarashi, T.; Nakai, T. Tetrahedron Lett. 1994, 35, 1913-1916.
18. R=22.3 min for (2R, 2R)-iv.