Iron-carbon bond energies

For example, the (ClgTPP)Fe- anion reacts with n-BuI, which provides a measure of the lower limit for the iron-carbon bond energy ... 

In aprotic solvents, direct electrochemical reduction of C02 (—2.23 V vs. SCE) yields carbon monoxide and carbonate ion.29 The (porT)Fe dianion also reduces C02 to CO, but at a less negative potential (-1.70 V).30 Hence, the estimated iron-carbon bond energy (—AGbF) for the (porT)Fera—C(0)0 dianion is at least 50 kJ mol-1 [—AGBF > 96.5(—1.70 + 2.23)]. 

In summary, the electrochemical results indicate that the alkyl-metal bond-formation free energies range from 54 to 146 kJ mol-1 for iron porphyrins and from 84 to 159 kJ mol-1 for cobalt porphyrins. The maximum bond energies are for primary alkyl groups bonded to [(MeO)4TPP]Con and (OEP)Fen porphyrins. The porphyrin dianions [(porT)nFe and (porr)nCo ] facilitate the reduction of C02 to CO via the transient formation of a metal-carbon bond [(por7)M—C(0)0- — AGBF > 50 kJ mol-1 for iron porphyrins]. Thus, iron and cobalt porphyrins are especially effective electrocatalysts for the reduction of C02 ... 

Transition metal catalysts, specifically those composed of iron nanoparticles, are widely employed in industrial chemical production and pollution abatement applications [67], Iron also plays a cracial role in many important biological processes. Iron oxides are economical alternatives to more costly catalysts and show activity for the oxidation of methane [68], conversion of carbon monoxide to carbon dioxide [58], and the transformation of various hydrocarbons [69,70]. In addition, iron oxides have good catalytic lifetimes and are resistant to high concentrations of moisture and CO which often poison other catalysts [71]. Li et al. have observed that nanosized iron oxides are highly active for CO oxidation at low tanperatures [58]. Iron is unique and more active than other catalyst and support materials because it is easily reduced and provides a large number of potential active sites because of its highly disordered and defect rich structure [72, 73]. Previous gas-phase smdies of cationic iron clusters have included determination of the thermochemistry and bond energies of iron cluster oxides and iron carbonyl complexes by Armentrout and co-workers [74, 75], and a classification of the dissociation patterns of small iron oxide cluster cations by Schwarz et al. [76]. 

Qiu, A. and D.T. Sawyer (1997). The electrochemical evaluation of the metal-carbon bond energies (—AGbf) of alkylated iron and cobalt porphyrins [(por)-M-R]. J. Porphyrins Phthalocyanines 1, 125-134. 

On W the metal-nitrogen bond energy is estimated to be 640 kJ mol irrespective of the surface orientation [24,25], about 60 kJ mol higher than for the Fe-N. Nitrogen, like carbon, dissolves interstitially into cc iron in small... 

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