Iron-molybdenum complex

Rh(PPrb(Cp) ] and the iron-molybdenum complex [FeMo(y-CCcH Me-4)-... 

Discussion. Molybdenum(VI) in acid solution when treated with tin(II) chloride [best in the presence of a little iron(II) ion] is converted largely into molybdenum(V) this forms a complex with thiocyanate ion, probably largely Mo(SCN)5, which is red in colour. The latter may be extracted with solvents possessing donor oxygen atoms (3-methylbutanol is preferred). The colour depends upon the acid concentration (optimum concentration 1M) and the concentration of the thiocyanate ion (1 per cent, but colour intensity is constant in the range 2-10 per cent) it is little influenced by excess of tin(II) chloride. The molybdenum complex has maximum absorption at 465 nm. 

Molybdenum hexafluoride. 3,1412 Molybdenum-iron-sulfur complexes, 4,241 Molybdenum oxide amino acid formation prebiotic systems, 6, 872 Molybdenum storage protein microorganisms, 6, 681 Molybdenum telluride, 3, 1431 Molybdenum tetraalkoxides physical properties, 2, 347 Molybdenum tribromide, 3,1330 Molybdenum trichloride, 3,1330 Molybdenum trifluoride, 3, 1330 Molybdenum trihalides, 3, 1330 bond lengths, 3, 1330 magnetic moments, 3,1330 preparation, 3,1330 properties, 3, 1330 structure, 3,1330 Molybdenum triiodide, 3,1330 Molybdenum trioxide complexes, 3, 1379 Molybdenum triselenide, 3, 143)... 

Sharma HK, Arias-Ugarte R, Metta-Magana AJ, Pannell KH (2009) Dehydrogenative dimerization of di-tert-butyltin dihydride photochemically and thermally catalyzed by iron and molybdenum complexes. Angew Chem Int Ed 48 6309-6312... 

N-Methylphenothiazine + iron or molybdenum complex Micellar effects upon rates and equilibria of electron transfer Minero et al., 1983... 

Figure 6.12 Structurally characterized iron-molybdenum dinitrogen complex. (Adapted from Figure 1 of reference 47.)...

Despite many applications of the iron-mediated carbazole synthesis, the access to 2-oxygenated tricyclic carbazole alkaloids using this method is limited due to the moderate yields for the oxidative cyclization [88,90]. In this respect, the molybdenum-mediated oxidative coupling of an arylamine and cyclohexene 2a represents a complementary method. The construction of the carbazole framework is achieved by consecutive molybdenum-mediated C-C and C-N bond formation. The cationic molybdenum complex, required for the electrophilic aromatic substitution, is easily prepared (Scheme 23). 

The molybdenum complex 1, a typical high-valent Schrock-type carbene, efficiently catalyzes the self-metathesis of styrene. On the other hand, the cationic iron complex 3 does not induce metathesis but stoichiometrically cyclopropanates styrene. The tungsten complex 2, again a Fischer-type carbene complex, mediates... 

Hunt s group (50, 51) have pioneered the application of the Cl source to organometallics such as the iron tricarbonyl complex of heptafulvene, whose electron impact spectrum shows (M—CO)+ as the heaviest ion, in contrast to the methane Cl spectrum with the ion as base peak. Boron hydrides (52) and borazine (53) have also been studied. The methane Cl spectrum of arenechromium and -molybdenum (54) show protonation at the metal giving a protonated parent or molecular ion. Risby et al. have studied the isobutane Cl mass spectra of lanthanide 2,2,6,6-tetramethylheptane-3,5-dionates[Ln(thd)3] (55) and 1,1,1,2,2,3,3-heptafluoro-7,7-dimethyl-4,6-oetanedione [H(fod)] lanthanide complexes (56). These latter complexes have been suggested as a means of analysis for the lanthanide elements. 

A large number of studies devoted to metal-sulfur centers are motivated by the occurrence of such arrangements at the active site of various metalloenzymes [1-13]. Mononuclear complexes with Mo=0 func-tion(s) and possessing sulfur ligands in their coordination sphere have been extensively investigated since they can be seen as models of the active site of enzymes such as nitrate- and DM SO reductases or sulfite- and xanthine oxidases [1-4]. On the other hand, a large variety of mono-, di-, and polynuclear Mo—S centers have been synthesized in order to produce functional models of the Mo-nitrogenase since the exact nature (mono-, di- or polynuclear) of the metal center, where N2 interacts within the iron-molybdenum cofactor (FeMo—co) of the enzyme is still unknown [4-8]. 

A large part of the research involving metal-sulfur complexes (metal = molybdenum or iron) is aimed at designing functional models of the active site of nitrogenase, the iron-molybdenum cofactor, EeMo—CO [4-8, 12, 13]. Only a very... 

More complex iron-sulfur clusters are also known to exist. These include the iron-molybdenum cofactor of nitrogenase (Thornely and Lowe, 1984) and probably larger clusters in which the only metal is iron (Hagen, 1987). They are characterized by highly anisotropic EPR spectra from S > ground states the nitrogenase cluster, for example is S = j and has EPR features near g = 4 and g = 2. 

HETEROBINUCLEAR NONACARBONYL COMPLEXES AND HYDRIDE COMPLEXES OF IRON-CHROMIUM, IRON-MOLYBDENUM, AND IRON-TUNGSTEN... 

The iron-molybdenum and iron-tungsten analogs are prepared in precisely the same manner with comparative yields of pure product. Well-formed crystals of [PPN]+ salts of the dinuclear dianion may be obtained by layering diethyl ether onto a concentrated CH3CN solution of dianion complex. 

PDB ID 1 N2C) (a) In this ribbon diagram, the dinitrogenase subunits are shown in gray and pink, the dinitrogenase reductase subunits in blue and green. The bound ADP is red. Note the 4Fe-4S complex (Fe atoms orange, S atoms yellow) and the iron-molybdenum cofactor (Mo... 

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