Liu Jiahao, Li Weikang, Li Yinwu, Liu Yan, Ke Zhuofeng
School of Materials Science and Engineering, PCFM Lab, School of Chemistry, Sun Yat-sen University, Guangzhou, 510275, P. R. China.
School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, 510006, P. R. China.
Chem Asian J. 2021 Oct 18;16(20):3124-3128. doi: 10.1002/asia.202100959. Epub 2021 Sep 16.
The first implementation of a molybdenum complex with an easily accessible bis-N-heterocyclic carbene ligand to catalyze β-alkylation of secondary alcohols via borrowing-hydrogen (BH) strategy using alcohols as alkylating agents is reported. Remarkably high activity, excellent selectivity, and broad substrate scope compatibility with advantages of catalyst usage low to 0.5 mol%, a catalytic amount of NaOH as the base, and H O as the by-product are demonstrated in this green and step-economical protocol. Mechanistic studies indicate a plausible outer-sphere mechanism in which the alcohol dehydrogenation is the rate-determining step.
报道了首例使用易于获得的双氮杂环卡宾配体的钼配合物，以醇为烷基化剂，通过借氢（BH）策略催化仲醇的β-烷基化反应。在这一绿色且步骤经济的反应中，展示出了极高的活性、出色的选择性和广泛的底物范围兼容性，具有催化剂用量低至0.5 mol%、催化量的NaOH作为碱以及H₂O作为副产物等优点。机理研究表明了一种合理的外层球机理，其中醇脱氢是速率决定步骤。
