Tetrakis complexes molybdenum

Hydrogen peroxide may be efficiently employed for the epoxidation of unfunctionalized aikenes in the presence of polyoxo complexes of tungsten and molybdenum . Venturello and coworkers first developed a phosphotungstate catalyst , with particular emphasis on the tetrakis(diperoxotungsto)phosphate anion P04[W(0)(02)2]4 , 37 , that in conjunction with H2O2 and a lipophilic tetra-alkylammonium salt Q+X as phase transfer... 

Tetrakis-/i-(carboxylato)-dimolybdenum(II) complexes have been obtained by only one general route, namely by the direct interaction of carboxylic acids with molybdenum hexacarbonyl.8 This reaction requires elevated reaction temperatures and prolonged reaction times. These same compounds are obtained in comparable or better yields by the brief reaction of tetrachloro- or tetrabromotetrakis(tributylphosphine)dimolybdenum(II) with alkyl- or aryl-carboxylic acids in refluxing benzene. The bis-/i-(arylcarboxylato) complexes... 

The resulting dark emerald green solution is filtered and the filtrate is concentrated to near dryness in vacuum. Diethyl ether (40 mL) is added and the solution is vigorously stirred to cause precipitation of the dark green molybdenum complex. The solution is filtered and the solid washed with two 5-mL portions of diethyl ether. The precipitate is dried in vacuum (10" 3 torr, 25 °C) to afford 3.36 g (90%) of dark emerald green cis-tetrakis(acetonitrile)-dinitrosylmolybdenum(II) bis[tetrafluoroborate(l —)]. 

The potentially six-coordinate ligands (edta)4- and (pdta)4" (H4edta = N,N,N, N tetrakis(2-ethanoic acid)-l,2-diaminoethane, H4pdta = N,N,N, iV -tetrakis(2-ethanoic acid)-1,2-diaminopropane) add to dimeric molybdenum(V) centres to form complexes such as [Mo202Y2(edta)]2- and [Mo02Y2(pdta)]2- (Y = O, S) 425-429 The structure of... 

I) Simple Monomeric Molybdenum Complexes. The first report on the synthesis of simple Mo dithio complexes appeared in 1971 when Mo(IV)(R2Dtc)4 complexes were obtained by CS2 insertion into Mo(NR2)4 complexes (68). Shortly after this report, the synthesis of these complexes from MoC14 and NaR2Dtc in acetonitrile was reported (88). A variety of tetrakis R2Dtc complexes of Mo(IV) also were obtained by the oxidative decarbonyla-tion of Mo(CO)6 with tetraalkyl thiuram disulfide (481,482, 609). 

Ethene, molybdenum complex, 26 102 rhenium complex, 26 110 Europium, tetrakis[T) -l, 3-bis(trimethyl-silyl)cyclopentadienyl]di-p.-chloro-di-, 27 171... 

OgNjCigHig, Acetic acid (1,2-ethanediyl-dinitTilo)tetra-, molybdenum complexes, 29 256,259 OgNiP4C32H44, Nickel(0), Tetrakis(dimethyl phenylphosphonite)-, 28 101... 

Molybdate, pentachlorooxy-stereochemistry, 50 Molybdate, tetrakis(dioxygen)-stereochemistry, 94 Molybdenum complexes history, 21... 

O22M03NiS8C2sH48 7H2O, Molybdenum, dec-aaquatetrasulfido-nickel-tri-, tetrakis(p-toluenesulfonate), heptahydrale, 33 156 O24CU5EUN18C45H55, Europium, 15-metaUa-crown-5 complex, 33 69 024Mn5Ni2C5sH78, Manganese(n), acetate, tetrakis[Mn(III)(salicylhydroximale)],... 

CbH,2Cl208Re2, Tetrakis(/x2"acetato)dichlorodirhenium, 46B, 1012 C8Hi2CrMo08, Chromiumdl) molybdenum(II) tetraacetate, 42B, 783 CBH12CU2O10, Copper(II) formate dioxan complex, 31B, 406 C8H12MO2O8, Dimolybdenum tetraacetate, 40B, 864 CbHi208U, Uranium(IV) acetate, 29, 458... 

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