[(1,2,5,6-η)-1,5-Cyclo­octa­diene](1-isopropyl-3-methyl­imidazolin-2-yl­idene)(triphenyl­phosphine)iridium(I) tetra­fluorido­borate dichloro­methane solvate

In the title compound, [Ir(C8H12)(C7H12N2)(C18H15P)]BF4·CH2Cl2, the Ir(I) atom has a square-planar conformation with normal bond lengths. One of the phenyl rings, and the solvent dichloro­methane mol­ecule, were refined using separate two part disorder models, each in an approximately 1:1 ratio

[(1,2,5,6-η)-Cyclo­octa-1,5-diene]bis­(1-isopropyl-3-methyl­imidazolin-2-yl­idene)rhodium(I) tetra­fluorido­borate

In the title compound, [Rh(C8H12)(C7H12N2)2]BF4, the square-planar Rh complex cation and the BF4 − anion are both bis­ected by a crystallographic twofold rotation axis. The Rh and B atoms lie on this axis and all others are in general positions. In the crystal, two unique C—H⋯F hydrogen-bonding inter­actions are present, which involve both imidazolin-2-yl­idene H atoms. They form two separate C(5) motifs, the combination of which is a rippled hydrogen-bonded sheet structure in the ab plane

A cationic rhodium(I) N-heterocyclic carbene complex isolated as an aqua adduct

The title complex, aqua­[1,3-bis­(2,6-diiso­propyl­phen­yl)imid­az­ol-2-yl­idene](η4-cyclo­octa-1,5-diene)rhodium(I) tetra­fluor­ido­borate, [Rh(C8H12)(C27H36N2)(H2O)]BF4, exihibits a square-planar geometry around the Rh(I) atom, formed by a bidentate cyclo­octa-1,5-diene (cod) ligand, an N-heterocylcic carbene and an aqua ligand. The complex is cationic and a BF4 − anion balances the charge. The structure exists as a hydrogen-bonded dimer in the solid state, formed via inter­actions between the aqua ligand H atoms and the BF4 − F atoms

[2-Butyl-4-(4-tert-butyl­benz­yl)-1,2,4-triazol-3-yl­idene]chlorido[(1,2,5,6-η)-cyclo­octa-1,5-diene]iridium(I)

In the title compound, [IrCl(C8H12)(C17H25N3)], the IrI ion has a distorted square-planar coordination geometry. The N-heterocyclic carbene ligand has an extended S-shaped conformation. The butyl group was refined using a two-part 1:1 disorder model. In the crystal, three unique weak C—H⋯Cl contacts are present. Two of these form a motif described as R 2 1(6) in graph-set notation, while a third forms an R 2 2(8) motif about a crystallographic inversion center. The result is a chain structure which extends parallel to the crystallographic a axis

Molybdenum, tungsten and rhodium complexes of nitrogen-oxides.

Complexes of the type MX(η²-NO₃)(CO)₂(PPh₃)₂, (M = Mo, X = Cl, Br; M = W, X = Br) were prepared from the reactions of MX₂(CO)₂(PPh₃)₂ with ammonium nitrate in acetone. The complexes were characterized by elemental analyses, ¹⁵N labelling, infrared and NMR spectroscopy. The nitrate ligand is bidentate and the complexes are seven-coordinate. Novel nitrite complexes of molybdenum and tungsten of the type M(NO₂)₂(PPh₃)₂ were prepared. The compounds were characterized by elemental analyses, ¹⁵N labelling, infrared and multinuclear NMR spectroscopy. Both NO₂ ligands are chelating and the two NO₂, PPh₃ and CO ligands are equivalent. Molybdenum dinitrosyl complexes were synthesized by the reduction of nitrate ions. The crystal structure of cis-dinitrosyl-cis-dichloro-trans-bis-(triphenylphosphine)molybdenum(II) was determined by x-ray diffraction. Both the nitrosyl groups are linear. Mo(NO)₂Cl₂(OPPh₃)₂ and Mo(NO)₂Cl(NO₃)(OPPh₃)₂ were synthesized by the reaction of MoCl(η²-NO₃)(CO)₂(PPh₃)₂ with NO in acetone/toluene mixture. The nitrosyl ligands are linear and the phosphineoxide ligands are cis to each other. The dinitrite complex Rh(NO)(NO₂)₂(PPh₃)₂ of the series Rh(NO)X₂(PPh₃)₂ (X - monodentate anions) was prepared as a direct derivative of Rh(NO)Cl₂(PPh₃)₂ by its reaction with sodium nitrite. The complex is square pyramidal with an apical nitrosyl ligand. The two NO₂ groups are present as the nitro and the nitrito group. Rh(NO)(NO₂)₂(PPh₃) reacted with oxygen and formed Rh(NO₃)₃(PPh₃)₂. The reaction of Rh(NO)(NO₂)₂(PPh₃)₂ with CO in acetonitrile produced Rh(CO)(NO₂)(PPh₃)₂. The complex Rh(CO)(NO₂)(PPh₃)₂ is square planar with the phosphine ligands in the trans positions

[(1,2,5,6-η)-Cycloocta-1,5-diene](1-ethyl-4-isopropyl-1,2,4-triazol-5-ylidene)(triphenylphosphane)iridium(I) tetrafluoridoborate dichloromethane sesquisolvate

The synthesis and crystal structure of a new triazole-based N-heterocyclic carbene iridium(I) cationic complex with a tetrafluoridoborate counter-anion and solvating dichloromethane, [Ir(C8H12)(C7H13N3)(C18H15P)]BF4·1.5CH2Cl2, is reported. The IrI center of the cationic complex has a distorted square-planar conformation, formed by a bidentate cycloocta-1,5-diene (COD) ligand, an N-heterocyclic carbene, and a triphenylphosphane ligand. There are weak hydrogen-bonding interactions between C—H groupings of the iridium complex and F atoms of the [BF4]− counter-ions. The atoms of the COD ligand are disordered over two sets of sites in a 0.65:0.35 ratio and two of the F atoms of the anion are disordered over adjacent sites in a 0.6:0.4 ratio. One of the dichloromethane solvent molecules is disordered about an inversion center with 0.5 occupancy

A cationic rhodium(I) N-heterocyclic carbene complex isolated as an aqua adduct

The title complex, aqua-[1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene] (η 4-cycloocta-1,5-diene)rhodium(I) tetrafluoridoborate, [Rh(C 8H 12)(C 27H 36N 2)(H 2O)]BF 4, exihibits a squareplanar geometry around the Rh(I) atom, formed by a bidentate cycloocta-1,5-diene (cod) ligand, an N-heterocylcic carbene and an aqua ligand. The complex is cationic and a BF 4- anion balances the charge. The structure exists as a hydrogenbonded dimer in the solid state, formed via interactions between the aqua ligand H atoms and the BF 4- F atoms

[(1,2,5,6-η)-Cycloocta-1,5-diene](1-ethyl-3-isopropyl-1,3-imidazol-2-ylidene-κC2)(triphenylphosphane-κP)iridium(I) tetrafluoridoborate

In the title compound, [Ir(C8H12)(C8H14N2)(C18H15P)]BF4, the cationic complex has the anticipated square-planar geometry. The asymmetric unit comprises the iridium complex and one tetrafluoridoborate anion. The space group is non-centrosymmetric, with the Flack parameter of 0.007 (3) well determined, and confirms the hand for the complex cation. This compound shows promising catalytic activity in transfer hydrogenation reactions