Photocatalytic anti-Markovnikov Chloroalkynylation of Unactivated Alkenes
Yun-Kai Wang1, Xin-Yu Yang1,2, Jie Zhou1,2
1School of Food and Biological Engineering, Hefei University of Technology, Hefei 230009, P. R. China.
Abstract:
A photoinduced three-component anti-Markovnikov chloroalkynylation of unactivated alkenes is enabled by proton-coupled electron transfer (PCET) using bench-stable HCl and alkynyl sulfones. A neutral acridine photocatalyst promotes cascade radical addition/fragmentation under mild conditions, delivering highly regioselective products otherwise difficult to access. The method accommodates diverse unactivated alkenes, including alkyl-substituted, 1,1-disubstituted, and drug-like derivatives. Diverse downstream derivatizations highlight the synthetic utility of these chloroalkyne building blocks.
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