Self-Assembly and Substituent Effect of Copper(I) Complexes with 1,2-Bis(2-pyridylethynyl)benzene Ligands

Abstract The reaction of 1,2-bis(2-pyridylethynyl)benzenes (L1–L5) with copper(I) ions proceeded smoothly to afford mononuclear copper(I) chelate complexes CL1–CL3 or dinuclear copper(I) molecular rectangular boxes, CL4 and CL5, in excellent yields, depending on the size of the substituent. If a ligand with a small substituent was used, the self-assembly of a mononuclear copper(I) chelate complex was achieved. If a ligand with a bulky substituent was used, the self-assembly of dinuclear copper(I) molecular rectangular boxes was achieved. The equilibrium between these two copper(I) complexes was also observed in solution.