Visible-Light-Activated Asymmetric Addition of Hydrocarbons to Pyridine-Based Ketones
作者:Han Yu、Tangyu Zhan、Yuqiao Zhou、Long Chen、Xiaohua Liu、Xiaoming Feng
DOI:10.1021/acscatal.2c00789
日期:2022.5.6
system involving Er(III)-based chiral Lewis acid catalysis, Ir(III)-based photoredox catalysis, and bromide-radical-mediated hydrogen atom transfer. The introduction of a bulky and nonredox chiral Lewis acid through the photoredox pathway enables the radical addition process and inhibits the above competitive reactions. The visible-light-promoted catalytic asymmetric alkylation of heteroaryl-based ketones
酮与烃的对映选择性光还原对于直接构建手性叔醇很有前景。但它通常由紫外光通过酮基自由基-烷基自由基偶联促进,其受到竞争性电荷转移过程和自/交叉自由基偶联反应的影响。需要选择可以改变反应途径并提供空间选择的手性催化剂。因此,我们公开了一种组合系统,包括基于 Er(III) 的手性路易斯酸催化、基于 Ir(III) 的光氧化还原催化和溴化物自由基介导的氢原子转移。通过光氧化还原途径引入体积庞大且非氧化还原的手性路易斯酸可以实现自由基加成过程并抑制上述竞争反应。