CHIRALITY IN UNSYMMETRICALLY SUBSTITUTED BENZOPENTATHIEPINS - THE RESULT OF A HIGH BARRIER TO RING INVERSION

被引：31

作者：

DAVIDSON, BS

FORD, PW

WAHLMAN, M

机构：

[1] Department of Chemistry University of Hawaii at Manoa, Honolulu

来源：

TETRAHEDRON LETTERS | 1994年 / 35卷 / 39期

关键词：

D O I：

10.1016/0040-4039(94)85356-8

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

The H-1 NMR spectrum of varacin (1), the first naturally-occurring compound determined to bear a 1,2,3,4,5-benzopentathiepin ring, shows unexpectedly complex signals for the side chain methylene protons. Evidence is presented which indicates that unsymmetrically substituted benzopentathiepins are asymmetric molecules as a result of a high energy barrier to inversion of the low energy chair conformations of the polysulfide ring. Derivatization of varacin with a chiral auxiliary provides diastereomeric products which can be separated by fractional recrystallization.

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页码：7185 / 7188

页数：4

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