Affiliation:
1. Kangwon National University
2. Oregon State Univetsity
3. Institute of Basic Science (IBS)
Abstract
Abstract
Functionalization of carboranes, icosahedral boron − carbon molecular clusters, is of great interest as they have wide applications in medicinal and materials chemistry. Thus, site- and enantioselective synthesis of carboranes requires complete control of the reaction. Herein, we describe the first asymmetric Rh(II)-catalyzed insertion reactions of carbenes into cage B − H bond of carboranes. This reaction thereby generates carboranes possessing a carbon-stereocenter adjacent to cage boron of the carborane, in excellent site- and enantioselectivity under mild reaction conditions. The first fully computed transition structures of Rh(II)-catalyzed carbene insertion process through density functional theory are reported. These B − H insertion transition structures, in conjunction with newly employed topographical proximity surfaces analyses, visually reveal the region between the carborane and the phthalimide ligands responsible for the selectivities of this reaction.
Publisher
Research Square Platform LLC
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