High-pressure nitrogen hydrides

Iron has a rich surface coordination chemistry that forms the basis of its important catalytic properties. There are many catalytic applications in which metallic iron or its oxides play a vital part, and the best known are associated with the synthesis of ammonia from hydrogen and nitrogen at high pressure (Haber-Bosch Process), and in hydrocarbon synthesis from CO/C02/hydrogen mixtures (Fischer-Tropsch synthesis). The surface species present in the former includes hydrides and nitrides as well as NH, NH2, and coordinated NH3 itself. Many intermediates have been proposed for hydrogenation of carbon oxides during Fischer-Tropsch synthesis that include growing hydrocarbon chains. 

Ammonia, the most important of the three hydrides of nitrogen, is one of the most important of all industrial chemicals. It is produced by the Haber process, which brings about the fixation of nitrogen by the direct combination of nitrogen and hydrogen under high pressure and in the presence of a catalyst ... 

Most reactions of bromine are highly exothermic which can cause incandescence or sudden increase in pressure and rupture of reaction flasks. There are a number of cases of explosions documented in the literature. (NFPA. 1986. Fire Protection Guide on Hazardous Materials, 9th ed. Quincy, MA National Fire Protection Association) Reactions of liquid bromine with most metals (or any metal in finely divided state), metal hydrides, carbonyls and nitrides can be explosive. Many oxides and halides of nonmetals, such as nitrogen triiodide or phosphorus trioxide, react explosively or burst into flame in contact with liquid bromine. 

This study, performed on the hydroformylation of oct-l-ene, has shown that below 140°C nonanals are the predominant products with linearities of approximately 97% (99% in one run at I00°C), whereas above 180°C nonanol was obtained almost exclusively with high octene conversions (>98% at 200°C) but poor linearities (65%). At high temperatures a 10-fold excess of bipy increases the nonanol linearity (to 76%). This parameter is not very sensitive to the CO or partial pressures as the total pressure is above about 95 bar. The author (40) seems to prefer coordination of the alkenc to a ruthenium center or hydride transfer to form an alkyl ruthenium cluster as the two possible rate-determining steps. Thus, by optimization of the experimental conditions it is possible to reach high linearities (n/iso>100) for the hydroformylation of terminal alkenes by the [Ru3(CO),2]/bidentate nitrogen- or phosphorus-containing ligand/phos-... 

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