Discrete copper() chalcogenones with metal-metal interaction

The Cu Cu interactions, known as cuprophilicity, play a significant role in copper-chalcogenide functional materials. Three dinuclear copper chalcogenone complexes, [( L 1 CuI) 2 ] ( 1 ), [( L 2 CuI) 2 ] ( 2 ) and [Cu 2 ( L 3 ) 4 ]PF 6 ( 3 ), have been isolated and characterized. L 1 = 1-(9-methyl anthracene)-2-isopropyl-benzimidazole-2-thione; L 2 = 1-(9-methyl anthracene)-2-isopropyl-benzimidazole-2-selenone and L 3 = 1-pyridine-2-isopropyl-imidazole-2-selenone, ligands and 1-3 were characterized by 1 H NMR, 13 C NMR, FT-IR, and SCXRD. Complexes 1 and 2 compress a four-membered strained ring system bridged by iodine, whereas 3 consists of a similar-four-membered ring core bridged by a selenium ligand. The Cu Cu interactions in the crystal structures are observed (2.591 Å for 1 , 2.576 Å for 2 , and 2.523 Å for 3 ). The bridging ligand shows a key contribution to the Cu Cu interactions. The density functional theory calculations also confirm the presence of d 10 d 10 interactions, which are predominantly covalent in nature. The computational study also shows the effect of the bridged ligands on the d 10 d 10 interactions and overall stability of the complexes, where complex 2 is the most stable followed by 1 , and after that 3 , although the d 10 d 10 interactions were the strongest in the case of 3 . Dinuclear copper( i ) chalcogenones with Cu-Cu interactions have been isolated and characterized by experimental and theoretical studies.