SYNTHESIS AND CHARACTERIZATION OF NEW HALOGEN TETRAMETHYLENE SULFOXIDE-RUTHENIUM(II) AND RUTHENIUM(III) COMPLEXES - CRYSTAL-STRUCTURE OF CIS-DICHLOROTETRAKIS(TETRAMETHYLENE SULFOXIDE)RUTHENIUM(II) AND HYDROGEN TRANS-BIS(TETRAMETHYLENE SULFOXIDE)TETRACHLORORUTHENATE(III)

In this paper we report the synthesis and characterization of the following ruthenium(II) and ruthenuium(III) complexes with tetramethylene sulfoxide (TMSO): cis-RuCl2(TMSO)4 (1), trans-RuCl2(TMSO)4 (2), the corresponding dibromo derivatives cis- and trans-RuBr2(TMSO)4 (3 and 4, respectively), (TMSO)H[trans-Ru(TMSO)2CL4] (5) and mer-RuCl3(TMSO)3 (6). Most of the reported complexes are described here for the first time, together with a new, easy synthetic path for the previously known complexes 1 and 3. The chemical behavior of 1 and 2 in solution of aprotic, non-coordinating solvents is described. Among the Ru(II) derivatives, the cis isomers are thermodynamically more stable and a photochemically driven cis to trans isomerization reaction is observed in tetramethylene sulfoxide solution. We also report the crystal structures of cis-RuCl2(TMSO)4 (1) and (TMSO)H]trans-Ru(TMSO)2Cl4[ (5), as determined by three dimensional X-ray analyses. Crystal data: 1, a = 9.104(2), b = 11.317(2), c = 21.867(6) angstrom, beta = 90.62(2)-degrees, monoclinic, space group P2(1)/c, Z = 4; 5, a = 14.642(4), b = 14.999(4), c = 9.667(4) angstrom, beta = 103.57(1)-degrees, monoclinic, space group P2(1)/c, Z = 4. Least-squares refinement based on 3813 (1) and reflections 4706(5) converged to R = 0.032 and 0.033 for 1 and 5, respectively. In 1, all the TMSO ligands are S-bonded to Ru, with average Ru-S bond distances of 2.355(6) (trans to S) and 2.273(1) (trans to Cl) angstrom. The TMSO ligands in 5 are both S-bonded to Ru (av. 2.33(1) angstrom). The protonated TMSO molecule is hydrogen bonded to one of the two crystallographically independent anions.