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Chiral Organometallic Reagents, VIII. On the Configurational Stability of α-Hetero-Substituted Benzyllithium Compounds

✍ Scribed by Hoffmann, Reinhard W. ;Rühl, Thomas ;Harbach, Jürgen

Publisher: John Wiley and Sons
Year: 1992
Tongue: English
Weight: 602 KB
Volume: 1992
Category: Article
ISSN: 0947-3440
DOI: 10.1002/jlac.1992199201122

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✦ Synopsis

Abstract

A test based on kinetic resolution was applied to probe the configurational stability of various α‐substituted benzyllithium compounds 1. It was found that the trimethylsilyl‐ (1b), phenylsulfenyl‐ (1c), and the phenylselenyl‐substituted (1d) benzyllithium compounds enantiomerized more rapidly than they added to the chiral aldehyde 6. In contrast, the carbamoyloxy‐ (1e), (16), and the phenylsulfonyl‐substituted (1g) benzyllithium compounds were found to be configurationally stable on the time scale set by their addition to the aldehyde 6.

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