Affiliation:
1. CAS Key Laboratory of Synthetic Chemistry of Natural Substances Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Shanghai 200032 China
2. School of Chemistry and Materials Science Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences Hangzhou 310024 China
Abstract
AbstractDifferent from classical allylic substitutions that require a vicinal leaving group, an olefin bearing a remote leaving group is scarcely viewed as a potential allylation substrate. Herein, we describe feasible protocols to achieve regiodivergent allylic C−H functionalizations via palladium‐catalyzed remote substitution, which provides a novel strategy for the seldomly studied migratory Tsuji–Trost reaction. Dictated by a suitable ligand, a process that involved 4,3‐hydrofunctionalization of the generated conjugated diene intermediate via metal walking is observed in generally >20 : 1 regioselectivity. Unexpectedly, a related 1,4‐hydrofunctionalization pathway is found to be a major route with a newly synthesized electron‐rich bisphosphine ligand, which challenges the conventional viewpoint on the potential regioselectivity of hydrofunctionalizations of linear internal conjugated dienes via η3‐substitution. A series of deuterium experiments and kinetic studies provide a preliminary insight into the potential catalytic cycle.
Funder
Science and Technology Innovation Plan Of Shanghai Science and Technology Commission
National Natural Science Foundation of China