Tris(1H-benzimidazol-2-ylmeth-yl)amine methanol tris-olvate.

The structure of the tertiary amine tris-(1H-benzimidazol-2-ylmeth-yl)amine (C24H21N7, abbreviated ntb) has been previously reported twice as solvates, namely the monohydrate and the aceto-nitrile-methanol-water (1/0.5/1.5) solvate, both with the tripodal conformation formed via multiple hydrogen bonds. Now, we report the tri-methanol adduct, ntb·3CH3OH, where the amine has the stair conformation featuring one benzimidazole group oriented in the opposite direction from the other two. The asymmetric unit contains one-half amine, completed through the mirror plane m in space group Pmn21 to form the ntb mol-ecule, with the H atom for each imidazole moiety equally disordered between both N sites available in the imidazole ring. The asymmetric unit also contains one and a half methanol mol-ecules, one being placed in general position with the hy-droxy H atom disordered over two sites with occupancy ratio 1:1, while the other lies on the m mirror plane, and has thus its hy-droxy H atom disordered by symmetry. As in the previously reported solvates, all imine and amine groups of the ntb mol-ecules and the methanol mol-ecules are involved in N-H⋯O and O-H⋯N hydrogen bonds. In the title compound, however, the involved H atom is systematically a disordered H atom provided by an imidazole group or a methanol mol-ecule.

Crystal structure of azido-(η(5)-cyclo-penta-dien-yl)bis-(tri-phenyl-phosphane-κP)ruthenium(II) di-chloro-methane hemisolvate.

The title solvated complex, [Ru(η(5)-C5H5)(N3){P(C6H5)3}2]·0.5CH2Cl2, displays a typical piano-stool geometry about the Ru(II) atom. The bond lengths and angles of the cyclo-penta-dienyl and phosphane ligands are very similar to that of the unsolvated complex [Taqui Khan et al. (1994 ▶). Acta Cryst. C50, 502-504]. The azide anion displays similar N-N distances of 1.173 (3) and 1.156 (3) Šand has an N-N-Ru angle of 119.20 (15)°, indicating a greater contribution of the canonical form Ru-N=N((+))=N((-)) for the bonding situation. An intra-molecular C-H⋯N hydrogen-bonding inter-action between one ortho H atom of a phosphane ligand and the N atom coordinating to the metal is observed. A similar inter-molecular inter-action is observed between a meta H atom of a phosphane ligand and the terminal azide N atom of a neighbouring complex. Finally, two C-H⋯N inter-actions exists between the H atoms of the di-chloro-methane solvent mol-ecule and the terminal N atom of two azide anions. The solvent mol-ecule is located about a twofold rotation axis and shows disorder of the Cl atoms with an occupancy ratio of 0.62 (3):0.38 (3).

Chloridotris(penta-fluoro-benzene-thiol-ato-κS)[tris-(4-fluoro-phen-yl)phosphine-κP]osmium(IV).

The title complex, [Os(C(6)F(5)S)(3)Cl(C(18)H(12)F(3)P)], displays a trigonal-bipyramidal Os(IV) coordination geometry with the S atoms of three thiol-ate ligands occupying the equatorial positions. The thiol-ate penta-fluoro-phenyl substituents are all placed above the equatorial plane, forming a claw-like cavity which accommodates the chloride ligand with a normal Os-Cl bond length. The phosphine ligand trans to the chloride ligand reveals a short Os-P bond length compared to other chloride-phosphine Os(IV) complexes (average = 2.40 Å). This strong bonding indicates that the inductive effect of the F atoms in the phosphine does not affect significantly its basicity, compared to triphenyl-phosphine. This feature is also consistent with the known poor trans influence of Cl(-). The crystal packing involves π-π contacts between inversion-related thiol-ate C(6)F(5) rings, with a centroid-centroid separation of 3.659 (8) Å.

Carbon-fluorine bond cleavage in the preparation of Osmium(III) and Osmium(IV) fluorothiolate complexes. Fluorine by fluorine NMR-assignment and fluxional processes.

Reactions of OsO4 with HSR (R=C6F5, C6F4H-4,) in refluxing ethanol afford [Os(SC6F5)3(SC6F4(SC6F5)-2)] (1) and [Os(SC6F4H-4)3(SC6F3H-4-(SC6F4H-4)-2)] (2), which involve the rupture of C-F bonds. At room temperature, the compound [Os(SC6F5)3(PMe2Ph)2] or [Os(SC6F5)4(PMe2Ph)] reacts with KOH(aq) in acetone, giving rise to [ Os(SC6F5)(SC6F4(SC6F4O-2)-2)(PMe2Ph)2] (3), through a process involving the rupture of two C-F bonds, while the compound [Os(SC6F4H)4(PPh3)] reacts with KOH(aq) in acetone to afford [Os(SC6F4H-4)2(SC6F3H-4-O-2)(PPh3)] (4), which also implies a C-F bond cleavage. Single-crystal X-ray diffraction studies of 1, 2, and 4 indicate that these compounds include five-coordinated metal ions in essentially trigonal-bipyramidal geometries, whereas these studies on the paramagnetic compound 3 show a six-coordinated osmium center in a distorted octahedral geometry. 19F, 1H, 31P{1H}, and COSY 19F-19F NMR studies for the diamagnetic 1, 2, and 4 compounds, including variable-temperature 19F NMR experiments, showed that these molecules are fluxional. Some of the activation parameters for these dynamic processes have been determined.

Tetrakis(pentafluorobenzenethiolato-kappaS)(triphenylphosphine-kappaP)osmium(IV): a Z' = 3 structure with a supramolecular double-stranded backbone.

The title complex, [Os(C6F5S)4(C18H15P)], crystallizes with three independent molecules in the asymmetric unit. Two of these have very similar conformations, while in the third, the axial thiolate ligand has a rotation that differs by ca 21.5 degrees . The coordination around the metal atom is trigonal bipyramidal and the supramolecular structure involves an unusual double-stranded backbone.

Conversion of [Pt(SRf)2(PPh2 -n(C6F5)n+ 1)2]( n = 0 or 1, Rf=C6HF4-4) through carbon-fluorine bond activation to [Pt(SRf)2(1,2-C6F4(SRf)-(PPh2))] and chiral [Pt(SRf)2(1,2-C6F4(SRf)(PPh(C6F5)))].

Treatment of trans-[PtCl(2)(PPh(2 - n)(C(6)F(5))(n + 1))(2)](n = 0 or 1) with Pb(SC(6)HF(4)-4)(2) yields a mixture of monometallic cis/trans [Pt(SC(6)HF(4)-4)(2)(PPh(2 - n)(C(6)F(5))(n + 1))(2)], thiolate-bridged bimetallic cis/trans [Pt(2)(mu-SC(6)HF(4)-4)(2)(SC(6)HF(4)-4)(2)(PPh(2 - n)(C(6)F(5))(n + 1))(2)] and [Pt(SC(6)HF(4)-4)(2)(1,2-C(6)F(4)(SC(6)HF(4)-4)(PPh(2 - n)(C(6)F(5))(n))].

Insertion reactions of [M(SR)3(PMe2Ph)2] with CS2 (M = Ru, Os; R = C6F4H-4, C6F5). X-ray structures of [Ru(S2CSC6F4H-4)2(PMe2Ph)2], trans-thiolates [M(SR)2(S2CSR)(PMe2Ph)2] (M = Ru; R = C6F5 and M = Os; R = C6F4H-4), and trans-thiolate-phosphine [Os(SC6F5)2(S2CSC6F5)(PMe2Ph)2].

Reactions of [M(SR)(3)(PMe(2)Ph)(2)] (M = Ru, Os; R = C(6)F(4)H-4, C(6)F(5)) with CS(2) in acetone afford [Ru(S(2)CSR)(2)(PMe(2)Ph)(2)] (R = C(6)F(4)H-4, 1; C(6)F(5), 3) and trans-thiolates [Ru(SR)(2)(S(2)CSR)(PMe(2)Ph)(2)] (R = C(6)F(4)H-4, 2; C(6)F(5), 4) or the isomers trans-thiolates [Os(SR)(2)(S(2)CSR)(PMe(2)Ph)(2)] (R = C(6)F(4)H-4, 5; C(6)F(5), 7) and trans-thiolate-phosphine [Os(SR)(2)(S(2)CSR)(PMe(2)Ph)(2)] (R = C(6)F(4)H-4, 6; C(6)F(5), 8) through processes involving CS(2) insertion into M-SR bonds. The ruthenium(III) complexes [Ru(SR)(3)(PMe(2)Ph)(2)] react with CS(2) to give the diamagnetic thiolate-thioxanthato ruthenium(II) and the paramagnetic ruthenium(III) complexes while osmium(III) complexes [Os(SR)(3)(PMe(2)Ph)(2)] react to give the paramagnetic thiolate-thioxanthato osmium(III) isomers. The single-crystal X-ray diffraction studies of 1, 4, 5, and 8 show distorted octahedral structures. (31)P [(1)H] and (19)F NMR studies show that the solution structures of 1 and 3 are consistent with the solid-state structure of 1.