Asymmetric Palladium Migration for Synthesis of Chiral‐at‐Cage <i>o</i>‐Carboranes
Chenyang Guo, Jie Zhang, Yixiu Ge, Zaozao Qiu, Zuowei Xie
Abstract
Abstract Metal migration strategy can offer BH functionalization of o ‐carboranes at different positions from where initial bond activation occurs to achieve bifunctionalized o ‐carboranes in one reaction. We report in this article an enantioselective 3,4‐bifunctionalization of o ‐carboranes via asymmetric Pd migration with a high efficiency and up to 98 % ee. This asymmetric catalysis has a broad substrates scope, leading to the preparation of a class of chiral‐at‐cage o ‐carborane derivatives. The enantiocontrol model is suggested on the basis of density functional theory (DFT) results, where the chiral Trost ligand plays a crucial role in this enantioselective Pd migration from exo ‐alkenyl sp 2 C to the cage B(4) position of o ‐carborane.