TRANSITION-METAL COMPLEXES WITH SULFUR LIGANDS .112. SYNTHESIS AND CHARACTERIZATION OF RUTHENIUM COMPLEXES WITH [RUPS2N2] CORES - SUBSTITUTION, REDOX, AND ACID-BASE REACTIONS OF [RU-II(L)(PR(3))(S2N2H2)] (L=CO, PPR3, R=PR OR CY) AND 5-COORDINATE [RU-IV(PCY(3))(S2N2)]

In order to find new ruthenium complexes with [RuPS2N2] frameworks, [Ru(PPr3)(2)('S2N2H2')] (2), ('S2N2H2'(2-) = 1,2-ethanediamine-N,N'-bis(2-benzenethiolate)(2-)), [Ru(CO)(PPr3)('S2N2H2')] (7), [Ru(CO)(PCy(3))('S2N2H2')] (4), [Ru(PCy(3))('S2N2')] (5), ('S2N2'(4-) = 1,2-ethanediamide-N,N'-bis(2-benzenethiolate)(4-)), [Ru(Br)(PPh(3))-('Et(2)S(2)N(2)H(2)')]Br (8), ('Et(2)S(2)N(2)H(2)' = 1,10-diethyl-2,3,8,9-dibenzo-1,10-dithia-4,7-diazadecane) and [Ru(Br)-(PPh(3))('(PhCH(2))(2)S2N2H2)]Br (9) ('(PhCH(2))(2)S2N2H2' = 1,10-dibenzyl-2,3,8,9-dibenzo-1,10-dithia-4,7-diazadecane) were synthesized. The molecular structures of 2, 5 and 9 were elucidated by X-ray structure determination. (2: triclinic space group P $($) over bar$$ 1; a = 11.103(3) Angstrom, b = 11.720(2) Angstrom, c = 13.813(3) Angstrom; alpha = 79.43(2)degrees, beta = 85.73(2)degrees, gamma = 82.91(2)degrees; Z = 2; R/R(w) = 5.1/4.6%. 5: monoclinic space group P2(1)/n; a = 12.019(4) Angstrom, b = 15.132(6) Angstrom, c = 33.566(11) Angstrom; beta = 90.56(3)degrees; Z = 8; R/R(w) = 5.0/4.7%. 9: monoclinic space group Cc; a = 17.839(9) Angstrom, b = 15.846(8) Angstrom, C = 15.706(10) Angstrom; beta = 109.18(5)degrees; Z = 4; R/R(w) = 6.0/6.0%.) 2 and 9 exhibit pseudooctahedral six-coordinate Ru(II) centers. The five-coordinate Ru(IV) center contained in 5 has a distorted coordination polyhedron, which can be described as trigonal bipyramid or tetragonal pyramid. The Ru(IV) oxidation state of 5 is stabilized by strong pi donation of the thiolato and the amido groups. The reversible conversion of the Ru(IV) complex 5 into the Ru(II) complex [Ru(CO)(PCy(3))('S2N2H2)] (4) requires the simultaneous transfer of electrons, protons and CO and can be achieved by reaction with formic acid. In protic solvents, 2 yields the Schiff base complex [Ru(PPr3)(2)(gma)] (10) (gma(2-) = 1,2-diiminoethane-N,N'-bis(2-benzenethiolate)(2-)) upon reaction with CO which functions as proton and electron acceptor. The analogous [Ru(PMe(3))(2)(gma)] (11) is formed by the reaction of the Ru(IV) complex 5 with PMe(3). Mechanisms for the conversions of 2 into 10 and 5 into 11 are discussed.