Decatungstate Catalyzed Photochemical Acetylation of C(sp3)-H Bonds
Qinglong Liu1, Yuzhen Ding1, Yuxi Gao1
1Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, Yunnan Provincial Center for Research & Development of Natural Products, School of Pharmacy, Yunnan University, Kunming 650091, China.
Abstract:
A direct acetylation of inert C(sp3)-H bonds was developed that was catalyzed by decatungstate under visible light irradiation and was followed by radical addition-disassociation with phenylsulfonyl ethanone oxime. The reaction displays site-selectivity in multiple C(sp3)-H bonds without prefunctionalization and directing groups. Various functional groups are well-tolerated and natural molecules are structurally feasible. CF3-modified phenylsulfonyl ethanone oxime was discovered to be necessary for enhancing the electrophilicity of imine and lowering the C-S bond cleavage energy.
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