Abstract Phenanthroline ligands bearing two biphenyl ( L1 ) or tetraarylbenzene L2 substituents have been synthetized and used to prepare bis‐phenanthroline copper(I) complexes. Steric constraints are limited in the case of biphenyl‐substituted ligand [Cu( 2 ](BF 4 has obtained by reaction with [Cu(CH 3 CN) ). In contrast, large enough totally prevent formation corresponding homoleptic complex....

Four new heteroleptic Cu(I) complexes based on 1, 2, 3-triazolyl-quinoline or quinoxaline and a chelating diphosphine were prepared fully characterised. The mononuclear derivatives absorb in the visible region, up to 600 nm, while dinuclear complex has long-tail absorption 800 showing an additional electronic state corroborated by theoretical calculations. Although methylene group between triaz...