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Updated: Nov 1, 2025

Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
o-Quinone methide with overcrowded olefin component as a dehydridation catalyst under aerobic photoirradiation
Daisuke Uraguchi1, Kohsuke Kato2, Takashi Ooi2
1Institute for Catalysis, Hokkaido University Sapporo 001-0021 Japan.
Abstract:
An o-quinone methide (o-QM) featuring an overcrowded olefinic framework is introduced, which exhibits dehydridation activity owing to its enhanced zwitterionic character, particularly through photoexcitation. The characteristics of this o-QM enable the operation of dehydridative catalysis in the oxidation of benzylic secondary alcohols under aerobic photoirradiation conditions. An experimental analysis and density functional theory calculations provide mechanistic insights; the ground-state zwitterionic intermediate abstracts a hydride and proton simultaneously, and the active oxygen species facilitate catalyst regeneration.
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