Tungsten complexes nitrogen

Differential scanning calorimetry has been used to measure89,90 the enthalpy of reaction for the displacement of a nitrogen donor ligand, L, from tungsten complexes [W(CO)6 L ] by carbon monoxide under isobaric conditions. The reaction is described by the equation... 

Hidai, M. (1999) Chemical nitrogen fixation by molybdenum and tungsten complexes, Coord. Chem. Rev., 185-186, 99-108. 

Nitrogen fixation by reaction of tungsten complex bonded to a N2 molecule... 

Tungsten and Nitrogen, Phosphorus, Arsenic, Antimony, and Bismuth—Complex Salts containing Vanadium—Carbides—Complex Cyanogen Derivatives— Compounds with Silicon, Titanium, 2areonium, and Boron. 

Bis-nitrogen donor ligand-substituted alkylidyne complexes such as 78 were found to be good alternatives as starting materials to the thermally labile tetracarbonyl complexes 44). Substitution of one pyridine ligand in the bispyridine-substituted complexes 78 occurs in the presence of excess chloride [Eq. (64)] 103). The anionic complexes 79 are stable in the presence of excess chloride but are too labile to be isolated in pure form. These complexes were used in the synthesis of stable alkylidyne alkene tungsten complexes [Eq. (180), Section IV,G]. With phosphines both pyridine ligands in 78 are substituted [Eq. (65)] 44). For PMej the reaction of the tetracarbonyl complex W(CPh)Br(CO)4 had previously been shown to... 

Keywords Dinitrogen complexes, Organo-nitrogen compounds, Nitrogen fixation, Molybdenum complexes, Tungsten complexes... 

AlTUD-1, a new mesoporous, Bronsted acidic aluminosilicate with ideal characteristics for catalyst immobilization was used for the noncovalent anchoring of hydride tungsten complex [WH2(ti -OOCCH3) (Ph2PCH2CH2PPh2)2][BPh4]. The immobilization was carried out by an adsorption process in liquid phase. The new materials were characterized by several techniques spectroscopic methods (ICP-AES, FT-IR and UVA is), X-ray techniques (XPS and XRD), isothermal nitrogen adsorption and elemental analysis. 

Frankenburger (23b) and coworkers have evaporated metal wires in the presence of gases. This calls to mind the classical study of Langmuir (23c) of the reaction between tungsten and nitrogen, which he showed to occur in the gas phase. Frankenburg found the reaction between iron and hydrogen to occur on the walls of the vessel. The conditions are complex but the method clearly merits further study. 

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