DISPROPORTIONATION REACTION OF RU2CL(MU-O2CCH3)4 WITH BBTP [BBTP = TERT-BUTYLBIS(2-THIENYL)PHOSPHINE] - X-RAY CRYSTAL-STRUCTURES OF RU2(MU-O)(MU-O2CCH3)2 (O2CCH3)2(BBTP)2 AND CIS-RU(O2CCH3)2(BBTP)2.CH2CL2

The reaction of Ru2Cl(mu-O2CCH3)4 With bbtp [bbtp = tert-butylbis(2-thienyl)-phosphine] in methanol under nitrogen leads to a disproportionation process with the formation of Ru2(mu-O)(beta-O2CCH3)2(O2CCH3)2(bbtp)2 (1) and cis-Ru(O2CCH3)2(bbtp)2 (2). In the presence of air compound 2 is very unstable in solution, giving compound 1. The X-ray crystal structures of 1 and the CH2Cl2 solvate of 2 have been determined. Compound 1 contains two ruthenium(III) atoms linked by two bridging acetate groups and one bridging oxo ligand; the pseudo-octahedral environment of each ruthenium atom is completed by one bidentate chelating acetate and one monodentate phosphine ligand. Compound 2.CH2Cl2 also has a pseudo-octahedral environment, with two monodentate bbtp ligands and two bidentate chelating acetate ligands giving a cis arrangement.