Bis(4-cyano­phenolato)[hydro­tris­(3,5-dimethyl­pyrazol­yl)borato]nitro­syl­molybdenum(II)–4-hydroxy­benzonitrile–dichloro­methane (1/1/1)

In the title compound, [Mo(C15H22BN6)(C7H4NO)2(NO)]·C7H5NO·CH2Cl2, the central MoII atom adopts a distorted cis-MoO2N4 octa­hedral geometry with the hydro­tris­(3,5-dimethyl­pyrazolylborate) anion attached to the metal in an N,N′,N′′-tridentate tripodal coordination mode. Two O-bonded 4-cyano­phenolate anions and a nitrosyl cation complete the coodination of the MoII atom. Two intra­molecular C—H⋯O and one C—H⋯N hydrogen bonds help to establish the configuration of the complex mol­ecule. The crystal structure is stabilized by inter­molecular C—H⋯N and C—H⋯O hydrogen bonds

(4-tert-Butyl­pyridine)­chlorido[hydro­tris­(3,5-dimethyl­pyrazol-1-yl)borato]nitro­sylmolybdenum(I) dichloro­methane monosolvate

In the title compound, [Mo(C15H22BN6)Cl(NO)(C9H13N)]·CH2Cl2, the MoI atom adopts a distorted MoClN5 octa­hedral geometry with the hydro­tris­(3,5-dimethyl­pyrazol­yl)borate anion in an N,N′,N′′-tridentate tripodal (facial) coordination mode. A 4-tert-butyl­pyrine ligand, chloride anion and a nitrosyl cation complement the coodination of the MoI atom and an intra­molecular C—H⋯Cl hydrogen bond helps to stabilize the configuration of the complex mol­ecule. The packing is stabilized by an inter­molecular C—H⋯Cl hydrogen bond involving the complex mol­ecule and the CH2Cl2 solvent mol­ecule

Formation of trimetallic compounds containing redox-active nitrosyl molybdenum tris(3,5-dimethylpyrazolyl)-borato groups. Schiff base complexes containing two molybdenum centres linked by <i>meta</i> hydroxy copper schiff base ligands

The reaction of [Mo(NO)Tp*Cl2] [Tp* = tris(3,5-dimethyl-pyrazolyl)borate] with copper(II) Schiff base complexes derived by condensation of two mole equivalents of 2,4-dihydroxybenzaldehyde with a diamine [1,2-C6H4(NH2)2, NH2(CH2)nNH2, n = 2-5] affords trimetallic species containing three potential redox centres. The IR, UV-vis and EPR spectroscopic properties of these compounds are described and it is shown that, with increasing polymethylene bridges of the Schiff base ligands, the complexes distort from planarity probably towards tetrahedral structures. From cyclic and differential pulse voltammetry it is shown that the trimetallic species primarily undergo two sequential one electron reduction associated with the reduction of [Mo(NO)Tp*Cl]+ centres. By determination of conproportionation constants for the mono-reduced species, it is established that there is very weak interaction between the two [Mo(NO)Tp*Cl]+ centres in the trimetallic complexes. It is also demonstrated that the meta-substituted [Mo(NO)Tp*Cl]+ centres reduce at potentials more anodic than their para-substituted analogues. Reduction potentials of these complexes are also shown to be solvent dependent

Synthesis and characterization of amido and amido(monoalkylamido)nitrosyl-[tris(3,5-dimethylpyrazolyl)borato]molybdenum complexes

The chloro-amido complex [Mo{HB(3,5-Me2C3HN2)3}(NO)Cl(NH 2)] was prepared by treating [Mo{HB(3,5-Me2C3HN2)3}(NO)Cl 2] with an excess of ammonia. The monoalkylamido complexes [Mo{HB(3,5-Me2C3HN2)3}-(NO)(NH 2)(NHR)] (R = Me, Et, Pr-n and Bu-n) were obtained by the reaction of [Mo{HB(3,5-Me2C3HN2)3}(NO)Cl(NH 2)] with the appropriate primary amines. The IR and 1H NMR spectra of the new complexes were investigated

Synthesis and characterization of a new mono-molybdenated metallo-ligand [Mo{HB(3,5-Me2C3HN2)3}(NO)Cl(OC 6H4PPh2-p)]

The "metallo-ligands" can be considered effectively as a modified triphenylphosphine ligand, and used to generate novel transtion metal complexes in which electron-transfer and magnetism is embedded within the stable ligand framework. A new mono-molybdenated metallo-ligand was synthesized and characterized by NMR (1H and 31P-{1H}), IR and mass spectroscopy techniques as a starting material in the search for designing novel bimetallic complexes exhibiting optoelectronic properties and development of non-linear optical materials that possess commercial device applications

Redox activity of bimetallic molybdenum and tungsten nitrosyls containing ligands based on 4-hydroxyphenylalkanols

The redox-active bimetallic complexes, [{M(NO)L<SUP>*</SUP>X}<SUB>2</SUB>Q] [L<SUP>*</SUP> = tris(3,5-dimethylpyrazolyl)borate, HB(3,5-Me<SUB>2</SUB>pyz)<SUB>3</SUB>; M = Mo, X = Cl or I; M = W, X = Cl; Q = OC<SUB>6</SUB>H<SUB>4</SUB>(CH<SUB>2</SUB>)<SUB>n</SUB>O (n = 1-3) or NHC<SUB>6</SUB>H<SUB>4</SUB>(CH<SUB>2</SUB>)<SUB>n</SUB>O (n = 2, 3)], have been prepared and characterized spectroscopically and electrochemically (cyclic voltammetry, coulometry). The electrochemical data indicate that there can be weak interactions between the two metal-based redox centres

Metal-metal interactions across symmetrical bipyridyl bridging ligands in binuclear seventeen-electron molybdenum complexes

A series of 17-electron mononuclear complexes [Mo(NO)L(Cl)X] and their binuclear counterparts [{Mo-(NO)LCl}<SUB>2</SUB>(μ-X)][L = tris(3,5-dimethylpyrazolyl) hydroborate; X = 3,3'-dimethyl-4,4'-bipyridine (3,3'-dmbipy), 1,2-bis(4-pyridyl)acetylene (bpac), 4,4'-azopyridine (azpy), 1,4-bis[2-(4-pyridyl)ethenyl]-benzene (bpeb) or 1,4-bis(4-pyridyl) benzene (bpb)] have been prepared. Electrochemical studies show that the reduction potentials of the mononuclear complexes are sensitive to the degree of unsaturation in the monodentate ligand X, whereas the oxidation potentials are virtually constant. This suggests that the redox orbital involved in the reductions have considerable ligand-based character whereas the oxidations are more strongly metal-centred. This is supported by the electrochemical properties of the binuclear complexes, where the oxidation potentials are in every case coincident but the splitting between the reduction potentials of the equivalent molybdenum centres varies from 0.16 V (X =bpeb) to 0.56 V (X =bpac). By contrast the splitting of the redox potentials of pentaammineruthenium(II) fragments at either end of 'extended' 4,4'-bipyridine analogues of this type is an order of magnitude smaller. This strong interaction between [Mo(NO)LCl] moieties is in part due to a planar conformation of the bridging ligands, even when they are in principle capable of free rotation, since changing the bridging ligand from 4,4'-bipyridine to 3,3'-dmbipy (which cannot be planar due to the steric effects of the methyl groups) results in a decrease in the splitting of the reduction potentials from 0.77 to 0.38 V. The EPR spectra of the binuclear complexes all show that the two unpaired electrons (one at each 17-electron molybdenum centre) are in fast exchange across the bridging ligand at room temperature