Metal Complexes Containing Enantiopure Bis(diamidophosphite) Ligands in Asymmetric Allylic Substitution and Hydroformylation Reactions

Abstract

Enantiopure bis(diamidophosphite) ligands with a heterocyclic terminal fragment derived from (R)- and (S)-N,N′-dimethyl-1,1′-binaphthyldiamine and bridging fragments derived from (S,S)-2,3-butanediol (a), (4R,5R)-4,5-di(hydroxymethyl)-2,2-dimethyl-1,3-dioxolane (b), and (R)- and (S)-1,1′-bi-2-naphthol (c) were used to prepare the palladium complexes with general formula [Pd(η3-2-CH3-C3H4)(P-P)][X] (X = PF6, 1a-(S;Sal,Sal;S), 1b-(R;Ral,Ral;R), 1b-(S;Ral,Ral;S), 1c-(R;Ral;R), 1c-(R;Sal;R); X = BPh4, 2a-(R;Sal,Sal;R), 2c-(R;Ral;R)), which have been fully characterized. The solid-state structure for complexes 1a-(S;Sal,Sal;S) and 1b-(R;Ral,Ral;R) has been determined by X-ray diffraction. The catalytic performance of the palladium complexes has been evaluated in asymmetric allylic alkylation and amination reactions with the benchmark substrate. The influence of the nature and absolute configuration of both the terminal and bridging fragments of the bis(diamidophosphite) ligands on the asymmetric induction is d...