Metal complexes with two different sulfur containing ligands—II

Abstract

The synthesis and characterization of a series of mixed l,l-/l,2-dithiolene complexes, M [S2C2(CN)2] [SüCNR*]* with z = -1, M = Ni, Cu, Pd, Pt and with 2 = 0, M = Ni, Cu, Au, M [S2C2(CN)2] [S2C N C N ]2' , M = N i, Pd, and N i[S 2C2(CN)2] [S2COC2H5] -are reported. Voltammetric studies in dichloromethane revealed that the mixed complexes could be oxidized in a one electron step, the half-wavepotentials of which were generally in the middle between those for the unmixed complexes. The C-N stretching frequencies observed in the i.r. spectra of the M [S2C2(CN)2] [S2CNR2]2 complexes are reported. the 1,1-and 1,2-dithiolato ligand system s. N ick e l bis-com plexes w ith tw o different 1,2-dithiolato ligands w ere rep o rted [l], and the exchange reactions of th ese and related 1,2-dithiolenes w ere studied with voltam m etric techniques [1,2], *Part-I. Ref. [5]. 7. H. C. Brinkhoff, Ree. Trav. Chim. 90,377 (1971). 8. (a). P. T. Beurskens, J. A . Cras and J, J, Steggerda, Inorg. Chem, 7, 810 (1968); (b), H. C. IN T R O D U C T IO N T h ere is a growing interest in m etal com p lex es containing tw o different sulfur donor ligands, especially th o se w ithBrinkhoff, Thesis, Nijmegen, 1970. 9. J. G. M. van der Linden,R ec. Trav. Chim. 90,1027 (1971).

Copper(I) and copper(III) diselenocarbamates

“…The CZN and metal-selenium stretching frequencies observed in the infrared spectra are given in Table I, together with those of the analogous sulfur compounds. The shifts to higher frequencies with increasing oxidation number of the central metal ion generally noted for the dithiocarbamato complexes (5,6,7,8), is here also observed for the diselenocarbamato compounds.…”

“…The redox reaction, with E½ = 0.24 V vs SCE, is a reversible one electron transfer process, because for the slope of log i(id-i)-1 vs E a value of 62 mV was measured. For the sulfur analog a reversible one electron transfer process with a half-wave potential of 0.44 V vs SCE has been found (7).…”

“…In view of these results and regarding the recent reports of the preparations of metal dithiocarbamates in unusual oxidation states (5,6,7,8), it seems promising to investigate the oxidation characteristics of the analogous seleno compounds.…”