1521024-66-7Relevant academic research and scientific papers
Spiroketal-based diphosphine ligands in Pd-catalyzed asymmetric allylic amination of Morita-Baylis-Hillman adducts: Exceptionally high efficiency and new mechanism
Wang, Xiaoming,Guo, Peihua,Han, Zhaobin,Wang, Xubin,Wang, Zheng,Ding, Kuiling
, p. 405 - 411 (2014)
Exceptionally high activity (with a TON up to 4750) of the palladium complexes of SKP ligand was discovered in the catalysis of asymmetric allylic amination of MBH adducts with aromatic amines. A comprehensive mechanistic study indicates that the unique structural features of the SKP ligand, with a long P···P distance in its solid-state structure, were favorable for allowing two P atoms to play a bifunctional role in the catalysis. Herein, one of the P atom forms a C-P σ-bond with the terminal carbon atom of allyl moiety as a Lewis base, and an alternative P atom coordinates to Pd atom. The cooperative action of organo- and organometallic catalysis discovered in the present catalytic system is most likely responsible for its high activity, as well as excellent regio- and enantioselectivities. The mechanism disclosed in the present catalytic system is distinct from most of the currently recognized mechanisms for Pd-catalyzed allylic substitutions.
