ISSN:
1434-193X
Keywords:
Optically active epoxy diols
;
Epoxidation
;
Titanium catalysis
;
High diastereoselectivity
;
Optically active hydroperoxy and hydroxy homoallylic alcohols
;
Chemistry
;
General Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The Ti-catalyzed epoxidation of optically active (S,S)-hydroperoxy homoallylic alcohols 2 affords the epoxy diol (S,R,S)-4 in high diastereoselectivity (d.r. up to 95:5), while the optically active hydroxy homoallylic alcohols (R,R)-3 are epoxidized by the β-hydroperoxy alcohol 5 under titanium catalysis to the corresponding epoxy (R,S,R)-diol 4 in a diastereomeric ratio up to 〉 99:1. This high diastereoselectivity is rationalized in terms of a rigid template for the oxygen transfer, in which the hydroperoxy alcohol 2 or 5 is ligated tridentately and the diol 3 bound bidentately to the titanium metal. Through these oxidative routes, both enantiomeric epoxy diols 4 are conveniently accessible.
Type of Medium:
Electronic Resource
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