Synthesis, crystal structures and spectroscopic properties of copper(I) complexes containing β-dialdiminato supporting ligands

Two mononuclear neutral copper(I) complexes, Cu(L1)PPh3 (1), Cu(L2)(PPh3)2 (2) ([L1]− = [{N(C6H3iPr2-2,6)C(H)}2CPh]−; [L2]− = [{N(C6H5)C(H)}2CPh]−) have been synthesized and structurally characterized by X-ray crystallography. In complex 1, the copper(I) atom is in a distorted three-coordinate trigonal planar environment, whereas in complex 2 with the less sterically hindered β-dialdiminato ligand, the copper(I) atom is the centre of a four-coordinate distorted tetrahedron. At room temperature complexes 1 and 2 in a film of PMMA exhibit green emission at 543 and 549 nm with lifetimes of 5.28 and 5.32 ns, respectively.