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)(PR3)(`S2N2H2')] (L = CO, PR3, R = Pr or Cy) and Five-Coordinate [Ru(IV)(PCy3)(`S2N2')]

Article abstract of DOI:10.1021/ic00123a006

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)(PCy3)(`S2N2H2')] (4), [Ru(PCy3)(`S2N2')] (5), (`S2N2'(4-) = 1,2-ethanediamide-N,N'-bis(2-benzenethiolate)(4-)), [Ru(Br)(PPh3)(`Et2S2N2H2')]Br (8), (`Et2S2N2H2' = 1,10-diethyl-2,3,8,9-dibenzo-1,10-dithia-4,7-diazadecane), and [Ru(Br)(PPh3)(`(PhCH2)2S2N2H2')]Br (9) (`(PhCH2)2S2N2H2' = 1,10-dibenzyl-2,3,8,9-dibenzo-1,10-dithia-4,7-diazadecane) were synthesized. The molecularstructures of 2, 5 and 9 were elucidated by X-ray structure determination. (2: triclinic space group P1-; a = 11.103(3) ?, b = 11.720(2) ?, c = 13.813(3) ?; α = 79.43(2)°, β = 85.73(2)°, γ = 82.91(2)°; Z = 2; R/Rw = 5.1/4.6%. 5: monoclinic space group P21/n; a = 12.019(4) ?, b = 15.132(6) ?, c = 33.566(11) ?; β = 90.56(3)°; Z= 8; R/Rw = 5.0/4.7%. 9: monoclinic space group Cc; a = 17.839(9) ?, b = 15.846(8) ?, c = 15.706(10) ?; β = 109.18(5)°; Z = 4; R/Rw = 6.0/6.0%). 2 and9 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 π donation of the thiolato and the amido groups. The reversible conversion of the Ru(IV) complex 5 into the Ru(II) complex [Ru(CO)(PCy3)(`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(PMe3)2(gma)] (11) is formed by the reaction of the Ru(IV) complex 5 with PMe3. Mechanisms for the conversions of 2 into 10 and 5 into 11 are discussed.