TRANSITION METAL COMPLEXES WITH SULFUR LI GANDS .109. SYNTHESIS AND REACTIVITY OF MESO-[RU(L)((TBU)S5('))] COMPLEXES WITH L=NO-, N2H4, NH(2)NHR (R=ME, PH), NH(2)NME(2), NH3, NH(2)PH, NHET(2) )-H-2=2,2'-BIS(2-MERCAPTO-3,5-DI-T-BUTYLPHENYLTHIO DIETHYLSULFIDE)(, CO, PR(3) (R=ME, PH, CY), PYR, CN)

In a search of transition metal complexes with sulfur dominated coordi nation spheres and free coordination sites for the binding of small mo lecules, [RU(L)('S-bu(5)')] complexes with the sterically demanding pe ntadentate thioether-thiolate ligand 'S-bu(5)'(2-) ('S-bu(5)'(2-)= cap to-3,5-di-t-butylphenylthio)diethylsulfide(2-)) have been synthesized. Reaction of [RuCl3(NO)(PPh(3))(2)] with 5-di(t-butyl)benzene-1,2-dith iolate,'S-bu(2)'(2-), yields the 16 electron complex [RU(NO)('S-bu(2)' )(2)](-) which is isolated as the NBu(4)(+)-salt, 1. According to the NMR spectra, 1 contains a two-fold axis or a mirror plane. Alkylation of 1 with bis(beta-bromethyl)sulfide under reflux leads stereoselectiv ely to meso-[Ru(NO)('S-bu(5)')]Br, [2]Br. Reaction of [2]Br with LiBEt (3)H yields the barely soluble binuclear complex [RU('S-bu(5)')](2), 3 , With RU('S-bu(5)')RU(NO)('S-bu(2)')('S-bu(2)'-C2H4SH)], 4, as a by-p roduct. 4 . THF, 4a, has been characterized by X-ray structure analysi s. Reactions of 3 with sigma-pi- and sigma-ligands yield mononuclear m eso-[Ru(L)('S-bu(5)')] complexes which have been isolated and characte rized with L = CO, PMe(3), PPh(3), PCy(3), pyr, CN-, 5-10, NH(2)NHPh, NH(2)NHMe, NH(2)NMe(2), NH(2)Ph und NHEt(2), 13-17. Complexes 5-10 are stable compounds. Complexes 13-17, however, are sensitive towards oxi dation and/or substitution. Coordination of L = N2H4 and NH3 to 3 lead s to insoluble [RU(L)('S-bu(5)')](x) complexes.