Syntheses, crystal structures and optical properties of heteroleptic copper(I) dithio/PPh3 complexes

New heteroleptic copper(I) dithiocarbamate and xanthate complexes of the general formula [(PPh3)2CuL] (L = N-(4-pyridyl)-N-furfuryldithiocarbamate L1 (1), thiomorpholinedithiocarbamate L2 (2), phenylpiperazinedithiocarbamate L3 (3), furfurylxanthate L4 (4) and pyridine-4-xanthate L5 (5) have been synthesized by metathesis reactions of the precursor complex [Cu(PPh3)2NO3] and potassium salts of the ligands (KL) in an equimolar ratio. These complexes have been characterized by elemental analysis and spectroscopy (IR, UV–Vis., 1H, 13C and 31P NMR), and their structures have been elucidated by X-ray crystallography. In all the five structures, the copper atoms are found to reside within a four coordinate (P2S2) distorted tetrahedral geometry. The non-linear optical properties of 1–5 and the electronic absorption bands of 1 and 5 have been studied by DFT and TD-DFT methods, respectively. All the complexes are strongly luminescent in dichloromethane solution at room temperature. The pressed pellet σrt values of ∼10−8–10−5 S cm−1 show their weakly conducting behavior.

Five new heteroleptic Cu(I) dithiocarbamate/xanthate-PPh3 complexes (1–5) have been synthesized and fully characterized, and their conducting, non-linear optical and luminescence properties investigated. All the complexes are intensely luminescent in CH2Cl2 solution at room temperature.Figure optionsDownload as PowerPoint slide