Generating Fischer-Type Rh-Carbenes with Rh-Carbynoids
Eric Palomo1,2, Akhilesh K Sharma1, Zhaofeng Wang1
1Institute of Chemical Research of Catalonia (ICIQ-CERCA), The Barcelona Institute of Science and Technology, Països Catalans 16, 43007 Tarragona, Spain.
Abstract:
We describe the first catalytic generation of Fischer-type acyloxy Rh(II)-carbenes from carboxylic acids and Rh(II)-carbynoids. This novel class of transient donor/acceptor Rh(II)-carbenes evolved through a cyclopropanation process providing access to densely functionalized cyclopropyl-fused lactones with excellent diastereoselectivity. DFT calculations allowed the analysis of the properties of Rh(II)-carbynoids and acyloxy Rh(II)-carbenes as well as the characterization of the mechanism.
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