The chelate-to-bridging shift of phosphane dipalladacycles: convenient synthesis of double A-frame tetranuclear complexes

Abstract

Palladacycles of the type [Pd₂(Ph₂PCH₂PPh₂-P,P)₂(C,N:C,N)] (C,N:C,N = bis(N-2,3,4-trimethoxybenzylidene)-4,4′-sulfonyldianiline or -4,4′-oxydianiline) can undergo a spontaneous slow chelate-to-bridging diphosphane coordination shift in solution. Following this strategy a tailor-made synthetic procedure was devised that culminates in isolation of double A-frame tetranuclear palladium complexes.