Regio- and Enantioselective Catalytic Monoepoxidation of Conjugated Dienes: Synthesis of Chiral Allylic cis-Epoxides
Ti(IV)-salan 4 catalyzes the diastereo- and enantioselective monoepoxidation of conjugated dienes using 30% H2O2 at rt or below even in the presence of other olefins and adjacent stereocenters. Its enantiomer, ent-4, provides access to the opposite diastereomer or enantiomer. The resultant chiral a...
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Published in | Organic letters Vol. 17; no. 4; pp. 1058 - 1061 |
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Main Authors | , , , , , |
Format | Journal Article |
Language | English |
Published |
WASHINGTON
American Chemical Society
20.02.2015
Amer Chemical Soc |
Subjects | |
Online Access | Get full text |
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Summary: | Ti(IV)-salan 4 catalyzes the diastereo- and enantioselective monoepoxidation of conjugated dienes using 30% H2O2 at rt or below even in the presence of other olefins and adjacent stereocenters. Its enantiomer, ent-4, provides access to the opposite diastereomer or enantiomer. The resultant chiral allylic epoxides, and the triols derived from them, are versatile synthetic intermediates as well as substructures present in many bioactive natural products. The epoxidation is highly specific for Z-olefins. For 1-acyl(silyl)oxypenta-2,4-dienes, epoxidation of the distal olefin is generally favored in contrast to the adjacent regioselectivity characteristic of Sharpless, peracid, and other directed epoxidations of hydroxylated dienes. |
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Bibliography: | NIH RePORTER ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 1523-7060 1523-7052 1523-7052 |
DOI: | 10.1021/acs.orglett.5b00281 |