Tungsten carbonyl complexes applications

FT-ICR, see Fourier-transform ion cyclotron resonance Fullerene[60], germanium-germanium addition, 10, 748 Fullerenes with cobalt, 7, 51 on cobalt Cp rings, 7, 73 inside metallodendrimers, 12, 401 microwave applications, 1, 334 Pd rc-complexes, 8, 348 Ru—Os complexes, 6, 830 with tungsten carbonyls, 5, 687 )2-Fullerenes, with platinum, 8, 634 Fulvalene actinide complex, synthesis, 4, 232 Fulvalene chromium carbonyls, synthesis and characteristics, 5, 264... 

Although Mo (II) and W(II) exhibit the most extensive seven-coordinate chemistry yet known (consistent with the application of the effective atomic number rule to these systems), a survey of the substituted metal carbonyl complexes of molybdenum and tungsten reveals no structural data for compounds of the type M(00)3(6-6)2 where 6-6 is a bidentate monoanionic ligand. No tungsten tricarbonyls of this type have been reported to date, but McDonald and co-workers have synthesized and studied the closely related W(CO)2(PPh3) (6-6)2 compounds where 6-6 is a chelating dithiocarbamate (7), xanthate, or dithiophos-phate (8). For molybdenum, the compounds Mo(CO)3(dtc)2(dtc = R2NCS2") (9) are examples of the M(CO)3(6-6)2 type as is Mo(CO)3-[S2P(i-Pr)2]2 (10), which has been well characterized in solution. 

Chemical routes involving the use of tungsten salts have been reported. W2C was claimed to be formed by the pyrolysis of an organometallic complex containing cyclopentadiene and carbonyl groups.8 The W2C formed was useful for ceramic applications such as wear resistant surfaces and cutting tools. The same phase was also prepared by the reduction of WC14 with sodium triethylborohydride.9 The material was formed as 1-5 nm-sized crystallites as shown by SEM and TEM. 

The chemistry of the dicarbonyl(7 -cyclopentadienyl)nitrosyl and the chloro-(i7 -cyclopentadienyl)dinitrosyl complexes of chromium, molybdenum, and tungsten [i.e., fT -CsHs)M(CO)j(NO)] and [(i7 -CsHs)M(NO)2Cl] has not been studied extensively, partly because of the various difficulties associated with their preparation. The procedures described below are of general applicability to all three metals and lead to the desired compounds in high yields. The carbonyl nitrosyl complexes are the synthetic precursors of the chloro nitrosyl complexes and so their preparation is described first. 

Chromium, Molybdenum, and Tungsten.— Applications of benchrotrenes and analogous Mo complexes in organic synthesis have been reviewed, and studies of the use of such complexes as catalysts for alkene polymerization, isomerization, and hydrogenation have been reported. Decomplexation of the arene ligand of benchrotrenes can be conveniently effected by treatment with boiling pyridine. Spectroscopic studies of ( -arene)M(CO)3 complexes have been described, including discussions of carbonyl vibrational spectra, ih 2 and... 

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