Silver(I)-mediated isomerisation of trans-[RuCl2(P-P)2] (P-P=4-membered ring chelate diphosphine ligand) and its application in the syntheses of [RuCl(L)(P-P)2]+ (L=neutral ligand)

Conversion of trans-[RuCl2(P-P)2] (P-P=4-membered chelate diphosphine) to cis is facilitated by treatment with AgOTf or AgBF4 in 1,2-dichloroethane, which gives mixtures of Ru–Cl–Ag heterobimetallic complexes with cis stereochemistry at Ru(II), characterised by 31P{1H} and 1H NMR spectroscopy and by FAB mass spectrometry. Treatment of these mixtures with neutral ligands (CO, CH3CN) gives cis-[RuCl(L)(P-P)2]+, whereas simultaneous treatment of trans-[RuCl2(P-P)2] with L and Ag(I) salt gives trans-[RuCl(L)(P-P)2]+.