Ketone-catalyzed photochemical C(sp3)-H chlorination
Lei Han1, Jibao Xia1, Lin You1
1Department of Biochemistry, UT Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9038, USA.
Abstract:
Photoexcited arylketones catalyze the direct chlorination of C(sp3)-H groups by N-chlorosuccinimide. Acetophenone is the most effective catalyst for functionalization of unactivated C-H groups while benzophenone provides better yields for benzylic C-H functionalization. Activation of both acetophenone and benzophenone can be achieved by irradiation with a household compact fluorescent lamp. This light-dependent reaction provides a better control of the reaction as compared to the traditional chlorination methods that proceed through a free radical chain propagation mechanism.
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