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DOI: 10.1039/A904100A (Paper) Reference Section for: Chem. Commun., 1999, 1791-1792

Enantioselective hydroxylation of benzylic C–H bonds by D4-symmetric chiral oxoruthenium porphyrins†

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Rui Zhang, Wing-Yiu Yu, Tat-Shing Lai and Chi-Ming Che

Abstract

A D4-symmetric chiral dioxoruthenium(VI) porphyrin can effect stoichiometric and catalytic enantioselective hydroxylation of benzylic C–H bonds to give enantioenriched aryl alcohols, the highest ee of 76% being attained in the catalytic oxidation of 4-ethyltoluene with 2,6-dichloropyridine N-oxide as terminal oxidant; the oxidations proceed via a rate-limiting H-atom abstraction to germinate a benzylic radical intermediate.

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