Nitrosyl complexes molybdenum

The amido nitrosyl molybdenum complex MoCI(Tp )(NO)-(NH2)] reacts with alcohols, yielding the bisalkoxo complexes [Mo(OR)2(Tp )(NO)] (R = Me, Et, "Pr, Bu), analyzed by IR and H-NMR spectroscopy.60 Topaloglu and McCleverty also reported the synthesis and characterization of amido- and amido(monoalkylamido)-Mo(Tp )(NO) species61 and of [MoCl-(Tp )(NO)(OC6H4PPh 2-p)].62... 

The first thionitrosyl complex was discovered by chance during an attempted synthesis of molybdenum nitrido complexes in the presence of a source of sulfur, tetrathiuram sulfide. " This work of Dilworth and Chatt was reported in 1974 and ultimately led to the syntheses of a range of Mo, Re and Os thionitrosyl complexes starting with the respective nitrido complexes.Nitrosyl complexes, like carbonyls, had been known for decades, and the more recent syntheses of thio-carbonyl complexes forebode the advent of thionitrosyl complexes. However, convenient synthetic routes based on analogies with syntheses of NO complexes were generally not available because the requisite precursors did not exist or were inconvenient to handle. Sulfiliminato complexes (M=N=SR2) of transition metals are as yet unknown. The chemistry of thionitrosyl complexes was the subject of a recent review. ... 

McCleverty, J.A., Seddon, D., Bailey, N.A., and Walker, N.W. (1976) The chemistry of cyclopentadienyl and related nitrosyl complexes of molybdenum, part 5. Dihalogenonitrosyl tris(pyazolyl)borato]molybdenum complexes, dieir alcoholysis, and the crystal and molecular structure of chloronitrosylisopropoxo[tris(4-chlotD-3,5-dimethylpyrazoyl)borato]molybdenum, J.Chem.Sco., Dalton Trans, 898-908. 

The nitrosyl carbonyls CpM(NO)(CO)2 [M=Cr (21, 7S), Mo (57), W (19)) can be made by the action of nitric oxide on [CpCr(CO)3]2, [CpMo(CO)3] , or [CpW(CO)3] , respectively. The chromium complex undergoes a Friedel-Crafts acetylation to give (CsH4COCH3)Cr(NO)(CO)2 (21). A series of molybdenum complexes CpMo(NO)l2L [L = PPh3, P(OPh)3, py, and bipy] has been made from L and [CpMo(NO)l2]2 (57). The cationic manganese species [CpMn(NO)(CO)2], obtained by the action of nitrite and acid on CpMn(CO)3, can be precipitated as the yellow hexafluorophosphate salt (51). With sodium borohydride this affords [CpMn(NO)(CO)]2 which probably contains bridging NO groups (see below) (58). The complex [CpMn(NO)S2] is probably similar in structure... 

Proust, A., Gouzerh, P. and Robert, F. (1993). Molybdenum Oxo Nitrosyl Complexes. 1. Defect... 

A number of other molybdenum(III) nitrosyl complexes have been reported. Addition of dithiocarbamate salt to [MoBr2(CO)4]2 in the presence of o-phenylene-bis(dimethylarsine) (diars) yields, [Mo(CO)(S2CNR2)2(diars)] (R = Me, Et), which in turn are oxidized by [NO]Bp4 to nitrosyls, [Mo(NO)-(S2CNR2)2(diars)]BF4 (Eq. 77) (886). A crystallographic study (R = Et) reveals... 

Carmona et al. (899) prepared another monomeric molybdenum(I) nitrosyl complex, mer-[Mo(NO)(PMe3)3(S2CNMe2)], from [MoCl(NO)(PMe3)4]. Further reaction with carbon monoxide yields frani-[Mo(NO)(CO)(S2CNMe2)(PMe3)2] via replacement of the phosphine trans to a molybdenum-sulfur bond (Eq. 78). 

The analogous reaction of 3 with W2(OrBu)6 gave a brown solution, from which a yellow, microcrystalline material could be isolated. Based on spectroscopic data the latter was formulated as [Cy7Si70i2]2W2(p-H)(0tBu) (158). Cleavage of the Mo = Mo triple bond in 157 occurred upon treatment of this compound with NO (two equivalents) to afford the dimeric nitrosyl molybdenum silsesquioxane complex [Cy7Si70i2]2Mo2(NO)2 (159). °°... 

CYCLOPENTADIENYL)NITROSYL chromium, MOLYBDENUM, AND TUNGSTEN COMPLEXES... 

NO, Nitrosyls, molybdenum and tungsten, 26 132, 133 NOC, Cyanate tungsten complex, 26 42 NOC4H7, 3-Butenamide nickel complex, 26 206 NOC4H , 2-Propenamide, 2-methyl-nickel complex, 26 205 NOC H, Benzoyl isocyanide chromium complex, 26 32, 34, 35 N04ReC16H, Perrhenate, tetrabutylam-monium, 26 391... 

These complexes are generally prepared by methods similar to those employed for the dinitrosyl compounds, treatment of a low-valent molybdenum compound with NO or a nitrosyl derivative being the principal method. Compounds and major physical properties are collected in Table 3. 

The largest group of molybdenum(II) complexes is constituted by the nitrosyls (oxidation states being assigned on the somewhat arbitrary assumption that nitrogen monoxide, as a ligand, is NO+). Tables 6 and 7 give a selection of the compounds discussed. 

Table 6 Nitrosyl Complexes of Molybdenum(II) (Excluding Pyrazolylborates)...

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