Lap Szeto

Binuclear (salen)osmium phosphinidine and phosphiniminato complexes

The preparation of a number of binuclear (salen)osmium phosphinidine and phosphiniminato complexes using various strategies are described. Treatment of [Os(VI)(N)(L(1))(sol)](X) (sol = H(2)O or MeOH) with PPh(3) affords an osmium(IV) phosphinidine complex [Os(IV){N(H)PPh(3)}(L(1))(OMe)](X) (X = PF(6)1a, ClO(4)1b). If the reaction is carried out in CH(2)Cl(2) in the presence of excess pyrazine the osmium(III) phosphinidine species [Os(III){N(H)PPh(3)}(L(1))(pz)](PF(6)) 2 can be generated. On the other hand, if the reaction is carried out in CH(2)Cl(2) in the presence of a small amount of H(2)O, a μ-oxo osmium(IV) phosphinidine complex is obtained, [(L(1)){PPh(3)N(H)}Os(IV)-O-Os(IV){N(H)PPh(3)}(L(1))](PF(6))(2)3. Furthermore, if the reaction of [Os(VI)(N)(L(1))(OH(2))]PF(6) with PPh(3) is done in the presence of 2, the μ-pyrazine species, [(L(1)){PPh(3)N(H)}Os(III)-pz-Os(III){N(H)PPh(3)}(L(1))](PF(6))(2)4 can be isolated. Novel binuclear osmium(IV) complexes can be prepared by the use of a diphosphine ligand to attack two Os(VI)≡N. Reaction of [Os(VI)(N)(L(1))(OH(2))](PF(6)) with PPh(2)-C≡C-PPh(2) or PPh(2)-(CH(2))(3)-PPh(2) in MeOH affords the binuclear complexes [(MeO)(L(1))Os(IV){N(H)PPh(2)-R-PPh(2)N(H)}Os(IV)(L(1))(OMe)](PF(6))(2) (R = C≡C 5, (CH(2))(3)6). Reaction of [Os(VI)(N)(L(2))Cl] with PPh(2)FcPPh(2) generates a novel trimetallic complex, [Cl(L(2))Os(IV){NPPh(2)-Fc-PPh(2)N}Os(IV)(L(2))Cl] 7. The structures of 1b, 2, 3, 4, 5 and 7 have been determined by X-ray crystallography.

An open-channel architecture assembly from the [Os3(CO)8{µ-η3-ONCPh(NC5H4)}2] cluster

A novel osmium cluster with an open-channel structure has been synthesised and characterised by X-ray diffraction.

CCDC 620989: Experimental Crystal Structure Determination

Related Article: Wai-Fun Yeung, Tai-Chu Lau, Xin-Yi Wang, Song Gao, L.Szeto, Wing-Tak Wong|2006|Inorg.Chem.|45|6756|doi:10.1021/ic060580m

N,N′‐Bis(tert‐butoxy­carbonyl)­thio­urea

The title compound, C11H20O4N2S, has a planar skeleton and its crystal structure is stabilized by extensive intermolecular (N—H⋯S) and intramolecular (N—H⋯O and C—H⋯O) hydrogen-bonding interactions.

cyclo-Bis­[2-methyl­sulfanyl-6-([1,3,4]­thia­diazol-2-yl­sulfanyl­methyl)­pyridinium] diperchlorate

In the title compound, C18H16N6S62+·2ClO4−, the macrocyclic cation shows a twisted conformation and possesses crystallographic twofold symmetry. This conformation is stabilized by intramolecular N—H⋯N and C—H⋯N hydrogen bonds. In the crystal, the cations and anions are connected through C—H⋯O hydrogen bonds.