Enantioselective Rh-Catalyzed Arylation of Cyclopropenes Based on DFTMC Strategy

The direct functionalization of the three-membered carbocycles (DFTMC) to form multisubstiuted enantioenriched cyclopropanes provides an alternative and flexible approach to the rapid construction and modification of the smallest carbocycles, which generally exist in the natural products, pharmacetical agents and synthetic chemical intermediates. Comparing to the traditional asymmetric cyclopropanation process, the DFTMC strategy represents an important challenge to establish the backbone in both desired diastereoselectivity and enantioselectivity due to the inherent ring stain of three-membered rings. On the other hand, the DFTMC strategy is very interesting because it allows the diastereoselectively and even enantioselectively afford a variety of mutilsubstituted cyclopropanes directly from a simple three-membered carbocycles, which fulfills the goal of the efficient synthesize in modern organic community.

Based on the DFTMC strategy, many groups and us also demonstrated the asymmetric carbometalation of cyclopropenes to the construction of the enantienriched multisubstituted cyclcopropane, during which, we presented one example that the nonfunctionalized cyclopropene could undergo the asymmetric carbozincation to afford the phenyl cyclopropane in 82:18 er. (Scheme 1, II-c) Herein, we report our recent progress on the Rh-catalyzed asymmetric arylation of cyclopropenes with commercially available aryl boronic acids in high diastereoselectivity and enantioselectivity under mild conditions.

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