H-bonding dependent phosphorescence in a mixed ligand copper(I) complex

Abstract

The mixed ligand copper(I) derivative [Cu(PPh3)2(κ2-O,O″-lact)] (1) (lact = L-(+)-lactate) has been prepared and fully characterized. NMR studies indicated the occurrence of a fluxional behavior involving the lactate anion, in solution. The α-hydroxycarboxylate ligand is responsible for the generation of a catemeric O–H⋯O(CO) H-bonding network that strongly influences the photophysical properties of 1, in the solid state. Indeed, when irradiated with UV light the title compound shows a bright phosphorescence, which as suggested by DFT calculations is strictly related to the abovementioned H-bonding network.