Rate and equilibrium constants for the addition of N-heterocyclic carbenes into benzaldehydes: a remarkable 2-substituent effect.
Rate and equilibrium constants for the addition of N-heterocyclic carbenes into benzaldehydes: a remarkable 2-substituent effect.
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DOI：
10.1002/anie.201501840
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发表时间：
2015-06-01
期刊：
影响因子：
--
通讯作者：
Smith AD
中科院分区：
文献类型：
--
作者：
Collett CJ;Massey RS;Taylor JE;Maguire OR;O'Donoghue AC;Smith AD
测定了n -芳基三唑- n -杂环卡宾（NHC）预催化剂与取代苯甲醛衍生物在催化和化学计量条件下生成3-（羟基苄基）唑加合物的反应速率和平衡常数。动力学分析和反应谱拟合表明，苯甲醛2取代基在这些反应中具有显著的作用，并为苯甲醛交叉反应的化学选择性提供了新的认识。
Rate and equilibrium constants for the reaction between N-aryl triazolium N-heterocyclic carbene (NHC) precatalysts and substituted benzaldehyde derivatives to form 3-(hydroxybenzyl)azolium adducts under both catalytic and stoichiometric conditions have been measured. Kinetic analysis and reaction profile fitting of both the forward and reverse reactions, plus onwards reaction to the Breslow intermediate, demonstrate the remarkable effect of the benzaldehyde 2-substituent in these reactions and provide insight into the chemoselectivity of cross-benzoin reactions.