Nickel/Photoredox-Catalyzed Methylation of (Hetero)aryl Chlorides Using Trimethyl Orthoformate as a Methyl Radical Source
作者:Stavros K. Kariofillis、Benjamin J. Shields、Makeda A. Tekle-Smith、Michael J. Zacuto、Abigail G. Doyle
DOI:10.1021/jacs.0c02805
日期:2020.4.22
represents a valuable transformation, but typically requires harsh reaction conditions or reagents. We report a radical approach for the methylation of (hetero)aryl chlorides using nickel/photoredox catalysis wherein trimethyl orthoformate, a common laboratory solvent, serves as a methyl source. This method permits methylation of (hetero)aryl chlorides and acyl chlorides at an early and late stage with
有机卤化物的甲基化代表了一种有价值的转化,但通常需要苛刻的反应条件或试剂。我们报告了一种使用镍/光氧化还原催化对(杂)芳基氯进行甲基化的激进方法,其中原甲酸三甲酯(一种常见的实验室溶剂)作为甲基源。该方法允许(杂)芳基氯和酰氯在早期和晚期甲基化,具有广泛的官能团兼容性。机理研究表明,原甲酸三甲酯通过从氯介导的氢原子转移产生的叔自由基 β 断裂作为甲基自由基的来源。