NEW CLASS OF CU(I) COMPLEXES WITH 2-THIOXOHEXAMETHYLENEIMINE (TCLH) AND GROUP-VA DONORS - CRYSTAL-STRUCTURE OF [CU(TCLH)2(ASPH3)BR]

A new class of mixed ligand complexes, of copper(I) hexamethyleneimine-2-thione (omega-thiocaprolactam, tclH) with triphenylphosphine and triphenylarsine is synthesized and characterized. The complexes may be formulated as [Cu(tclH)2(EPh3)X], where E = P or As; X = Cl, Br or I. The arsine complexes express a remarkable photostability compared to their phosphine counterparts. Moreover, they do not react with stoichiometric amounts of pyridine which, in the case of the phosphine complexes displaces the thione ligands coordinated to copper. Furthermore, the crystal structure of the complex [Cu(tclH)2(AsPh3)Br], which is also discussed is the first one to present a mixed ligand arsine-thione copper(I) complex. The compound crystallizes in the P2(1)/n space group, with a = 18.704(1), b = 10.855(1), c = 15.593(1) angstrom and beta = 92.70(1)-degrees. A distorted tetrahedral environment around copper is present, with the two Cu-S bonds almost equivalent (2.310(1) and 2.315(1) angstrom). The Cu-As bond distance is equal to 2.371(1) angstrom and the Cu-Br bond length is 2.605(1) angstrom.