Cobalt-Catalyzed Markovnikov-Selective Radical Hydroacylation of Unactivated Alkenes with Acylphosphonates
作者:Benxiang Zhang、Jiayan He、Yi Li、Tao Song、Yewen Fang、Chaozhong Li
DOI:10.1021/jacs.1c02629
日期:2021.4.7
Acylphosphonates having the 5,5-dimethyl-1,3,2-dioxophosphinanyl skeleton are developed as efficient intermolecular radical acylation reagents, which enable the cobalt-catalyzed Markovnikov hydroacylation of unactivatedalkenes at room temperature under mild conditions. The protocol exhibits broad substrate scope and wide functional group compatibility, providing branched ketones in satisfactory yields
Several α-hydroxyphosphonates have been prepared by the Pudovik reaction of the cyclic phosphite 5,5-dimethyl-1,3,2-dioxaphosphinan-2-one with aldehydes and β-oxo aldehydes. These can be readily converted to α-chloro- or α-bromophosphonates in excellent yield by simply treating them with thionyl chloride or bromide. Reaction with phosphorus triiodide gave α-iodophosphonates and α-hydridophosphonates. The Pudovik products are obtained from β-oxo aldehydes can be readily dehydrated to give vinylphosphonates.