Alkynylation of Csp2 (O)-H Bonds Enabled by Photoredox-Mediated Hydrogen-Atom Transfer
Satobhisha Mukherjee1, R Aleyda Garza-Sanchez1, Adrian Tlahuext-Aca1
1Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstrasse 40, 48149, Münster, Germany.
Abstract:
The development of new hydrogen-atom transfer (HAT) strategies within the framework of photoredox catalysis is highly appealing for its power to activate a desired C-H bond in the substrate leading to its selective functionalization. Reported here is the first photoredox-mediated hydrogen-atom transfer method for the efficient synthesis of ynones, ynamides, and ynoates with high regio- and chemoselectivity by direct functionalization of Csp2 (O)-H bonds. The broad synthetic application of this method has been demonstrated by the selective functionalization of C(O)-H bonds within complex molecular scaffolds.
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