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Mitsunobu reactions of glycals with phenoxide nucleophiles are SN2′-selective

✍ Scribed by Aditya Sobti; Gary A. Sulikowski

Book ID: 104214290
Publisher: Elsevier Science
Year: 1994
Tongue: French
Weight: 294 KB
Volume: 35
Category: Article
ISSN: 0040-4039
DOI: 10.1016/s0040-4039(00)73065-6

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✦ Synopsis

The Clhydroxyl group of Lrhamnal( 4) and D-glucal7 underwent S,$!'-selective Mitsnnobu displacements with substituted phenoxide nucleophiles. These reactions provide access to the corresponding a-arylglycoside.

We required a method for the preparation of a-O-a@ glycoside of 2.3.6~trideoxy sugars in connection with planned syntheses of angucycline antibiotics. 1 A direct preparation starts with a substituted glycal and requires an allylic displacement of the C3-hydroxyl in preference to direct nucleophilic attack. This transformation would serve to eliminate the C3 substituent and simultaneously introduce an oxidatively

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