Synthesis and reactivity of dinuclear copper(i) pyridine diimine complexes

Abstract

The reaction of a tethered pyridine diimine (PDI) ligand with copper(I) chloride yielded a μ-chlorido bridged cationic dicopper(I) PDI complex, which is a rare structural motif. The geometric constraint of the ligand is fostering attractive van der Waals interactions between the coplanar pyridine units. This is supported by an Atoms in Molecules (AIM) and NCI (non-covalent interaction) analysis. Reaction with carbon monoxide yields the corresponding mono- and dicarbonyl complexes, which display reversible binding of carbon monoxide. This equilibrium was studied by ¹³C-NMR exchange spectroscopy and complemented by DFT and LNO-CCSD(T) calculations.