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Synthesis of Sterically Congested Carbonyl Compounds via an ipso-Selective Sulfonium Rearrangement
Immo Klose1, Christian Knittl-Frank1, Nicolas G-Simonian1
1Institute of Organic Chemistry, University of Vienna, Währinger Straße 38, 1090 Vienna, Austria.
Abstract:
Despite the success of metal-catalyzed cross-coupling strategies to assemble a variety of C-C bonds, the synthesis of sterically congested α-arylated carbonyl compounds remains a difficult task. Herein, we present an ipso-rearrangement approach relying on electron redistribution in sulfonium intermediates. This modular method enables the synthesis of a variety of α-arylated carbonyl compounds and is orthogonal to traditional metal-catalyzed cross-coupling strategies. More importantly, it demonstrated remarkable robustness toward steric hindrance and allowed us to efficiently forge congested C-C bonds.
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