Heterobimetallic Silver(I) and Copper(I) pyrazolates supported with 1,1′-bis(diphenylphosphino)ferrocene

• Neutral Ag(I) and Cu(I) pyrazolate complexes with 1,1′-bis(diphenylphosphino)ferrocene (dppf) were designed, in which dppf ligand possesses both chelating and bridging coordination modes. • Cationic Cu(I) complexes with non-deprotonated pyrazole and 1,1′-bis(diphenylphosphino)ferrocene or bis[(2-diphenylphosphino)phenyl] ether ligands were obtained. • Complexes possess two different electronic transitions involving Fe and Ag/Cu atoms. • TD-DFT calculations qualitatively describe the electronic transitions observed. Complexation of trinuclear silver(I) and copper(I) pyrazolates with chelated bisphosphines (1,1′-bis(diphenylphosphino)ferrocene (dppf) and bis[(2-diphenylphosphino)phenyl] ether (POP)) was investigated for the first time. The complexes of different structure were obtained depending on the reagent ratios. Deficiency of dppf ligand leads to the rearrangement of the trinuclear core to dinuclear, in which the metal atoms are bridged by bisphosphine. When bisphosphine is taken in a significant excess, the cyclic core rearranges to the linear complex featuring chelating and bridging 1,1′-bis(phosphino)ferrocenes and κ 1 coordinated pyrazolate anion. The electronic transitions observed in these complexes are qualitatively described by TD-DFT calculations.