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Updated: Jun 5, 2025
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[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
Published on: May 21, 2019
Site-Selective C(sp3)-H and Switchable C(sp3)-H/C(sp2)-H Functionalization Enabled by Electron-Deficient
Yuki Hirata1,2, Shunsuke Kimura2, Kosuke Higashida2
1Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-ku, Sapporo, Japan.
Abstract:
A site-selective functionalization of a C(sp3)-H bond was achieved in the presence of an intrinsically more reactive C(sp2)-H bond by controlling the orientation of a directing group via a photo-induced E/Z isomerization of an oxime ether. By combining E/Z isomerization and an electron deficient Cp*CF3Ir(III) catalyst, the scope of oxime ethers in C(sp3)-H functionalization was successfully expanded. Based on this strategy, the order of C-H activation was switchable and successive C(sp3)-H/C(sp2)-H and C(sp2)-H/C(sp3)-H double functionalizations were accomplished to construct densely functionalized structures.
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