The Chemistry of a,p-Unsaturated Sulfoxides

Nonracemic unsubstituted a,P-unsaturated sulfoxides 196 Nonracemic substituted a,P-unsaturated sulfoxides 197 

Orcanosulfur Chemistry. Copyright 1998 Academic Press Ltd. ISBN 0-12-543562-2. 

The synthetic utility of the sulfoxide functionality is well established in organic chemistry and has been known for many years [1]. More specifically, the use of nonracemic sulfoxides in asymmetric synthesis has assumed growing importance in recent years since the chiral sulfoxide group is often able to exert significant stereochemical control in bond-forming reactions. Such advances in asymmetric synthesis have been made possible by the development of new methodology for the preparation of nonracemic sulfoxides. 

This review is concerned with the use of a,P-unsaturated sulfoxides in organic synthesis and covers the chemistry of vinyl (alkenyl) and dienyl sulfoxides. Other types of a,P-unsaturated sulfoxides such as allenyl and propargyl (alkynyl) sulfoxides are beyond the scope of this review. Particular emphasis is given to the use of nonracemic a,P-unsaturated sulfoxides throughout, reflecting recent developments in this field. 

The methods available for the preparation of optically active a,P-unsaturated sulfoxides are discussed, including the asymmetric synthesis of dienyl sulfoxides, as most of the subsequent work discussed in this chapter is concerned with the use of the sulfoxide group as a stereocontrolling element in synthesis. 

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This review continues from one entitled The Chemistry of a,P-Unsaturated Sulfoxides which was recently published in a monograph of organosulfur chemistry. 1 In addition, the coverage has been extended to include the analogous a,P-unsaturated sulfones. The focus of the present review are recent advances in the chemistry of a,P-unsaturated sulfoxides and sulfones, especially those which have been published since 1993. The synthesis of a,P-unsaturated sulfoxides and sulfones has already been reviewed extensively by Rayner2 and hence will not be covered here. Only the chemistry of vinyl (alkenyl) sulfoxides and sulfones will be considered. The chemistry of other a,P-unsaturated sulfoxides and sulfones such as dienyl, allenyl, and propargyl (alkynyl) sulfoxides and sulfones is beyond the scope of this review. Considerable emphasis has been placed on stereo- and enantioselective reactions, reflecting the current interest in this area. 

RECENT ADVANCES IN THE CHEMISTRY OF a,P-UNSATURATED SULFOXIDES AND SULFONES Ian Forristal and Christopher M. Rayner 155... 

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