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Abstract: One of the most fundamental properties in chemistry is the bond dissociation energy, the energy required to break a specific bond of a molecule. In this paper, the Fe–N homolytic bond dissociation energies [ΔHhomo(Fe–N)'s] of 2 series of (meta‐substituted anilinyl)dicarbonyl(η5‐cyclopentadienyl) iron [m‐G‐C6H4NHFp (1)] and (meta‐substituted α‐acetylanilinyl)dicarbonyl(η5‐cyclopentadienyl) iron [m‐G‐C6H4N(COMe)Fp (2)] were studied using density functional theory methods with large basis sets. In this study, Fp is (η5‐C5H5)Fe(CO)2, and G is NO2, CN, COMe, CO2Me, CF3, Br, Cl, F, H, Me, MeO, and NMe2. The results show that Tao‐Perdew‐Staroverov‐Scuseria, Minnesota 2006, and Becke's power‐series ansatz from 1997 with dispersion corrections functionals can provide the best price/performance ratio and accurate predictions of ΔHhomo(Fe–N)'s. The ΔΔHhomo(Fe–N)'s (1 and 2) conform to the captodative principle. The polar effects of the meta‐substituents show the dominant role to the magnitudes of ΔΔHhomo(Fe–N)'s. σα· and σc· values for meta‐substituents are all related to polar effects. Spin‐delocalization effects of the meta‐substituents in ΔΔHhomo(Fe–N)'s are small but not necessarily zero. RE plays an important role in determining the net substituent effects on ΔHhomo(Fe–N)'s. Insight from this work may help the design of more effective catalytic processes. [ABSTRACT FROM AUTHOR]

The knowledge of accurate bond strengths is a fundamental basis for a proper analysis of chemical reaction mechanisms. Quantum chemical calculations at different levels of theory have been used to investigate heterolytic Fe-O and Fe-S bond energies of (meta-substituted phenoxy)dicarbonyl(η5-cyclopentadienyl) iron [ m-G-C6H4OFp ( 1)] and (meta-substituted benzenethiolato)dicarbonyl(η5-cyclopentadienyl) iron [ m-G-C6H4SFp ( 2)] complexes. In this study, Fp is (η5-C5H5)Fe(CO)2, and G is NO2, CN, COMe, CO2Me, CF3, Br, Cl, F, H, Me, MeO, and NMe2. The results show that Tao-Perdew-Staroverov-Scuseria and Becke's power-series ansatz from 1997 with dispersion corrections functionals can provide the best price/performance ratio and accurate predictions of Δ Hhet(Fe-O)'s and Δ Hhet(Fe-S)'s. The excellent linear free energy relations [ r = 1.00 (g, 1e), 1.00 (g, 2b)] among the ΔΔ Hhet (Fe-O)'s and δΔ G0 of OH bonds of m-G-C6H4OH or ΔΔ Hhet(Fe-S)'s and Δp Ka's of SH bonds of m-G-C6H4SH imply that the governing structural factors for these bond scissions are similar. And, the linear correlations [ r = −0.97 (g, 1 g), −0.97 (g, 2 h)] among the ΔΔ Hhet (Fe-O)'s or ΔΔ Hhet(Fe-S)'s and the substituent σm constants show that these correlations are in accordance with Hammett linear free energy relationships. The inductive effects of these substituents and the basis set effects influence the accuracy of Δ Hhet(Fe-O)'s or Δ Hhet(Fe-S)'s. The ΔΔ Hhet(Fe-O)'s(g) (1) and ΔΔ Hhet(Fe-S)'s(g)(2) follow the capto-dative Principle. The substituent effects on the Fe-O bonds are much stronger than those on the less polar Fe-S bonds. Insight from this work may help the design of more effective catalytic processes. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The knowledge of accurate bond strengths is a fundamental basis for a proper analysis of chemical reaction mechanisms. Quantum chemical calculations at different levels of theory have been used to investigate heterolytic Fe-O and Fe-S bond energies of (meta-substituted phenoxy)dicarbonyl(η5-cyclopentadienyl) iron [ m-G-C6H4OFp ( 1)] and (meta-substituted benzenethiolato)dicarbonyl(η5-cyclopentadienyl) iron [ m-G-C6H4SFp ( 2)] complexes. In this study, Fp is (η5-C5H5)Fe(CO)2, and G is NO2, CN, COMe, CO2Me, CF3, Br, Cl, F, H, Me, MeO, and NMe2. The results show that Tao-Perdew-Staroverov-Scuseria and Becke's power-series ansatz from 1997 with dispersion corrections functionals can provide the best price/performance ratio and accurate predictions of Δ Hhet(Fe-O)'s and Δ Hhet(Fe-S)'s. The excellent linear free energy relations [ r = 1.00 (g, 1e), 1.00 (g, 2b)] among the ΔΔ Hhet (Fe-O)'s and δΔ G0 of OH bonds of m-G-C6H4OH or ΔΔ Hhet(Fe-S)'s and Δp Ka's of SH bonds of m-G-C6H4SH imply that the governing structural factors for these bond scissions are similar. And, the linear correlations [ r = −0.97 (g, 1 g), −0.97 (g, 2 h)] among the ΔΔ Hhet (Fe-O)'s or ΔΔ Hhet(Fe-S)'s and the substituent σm constants show that these correlations are in accordance with Hammett linear free energy relationships. The inductive effects of these substituents and the basis set effects influence the accuracy of Δ Hhet(Fe-O)'s or Δ Hhet(Fe-S)'s. The ΔΔ Hhet(Fe-O)'s(g) (1) and ΔΔ Hhet(Fe-S)'s(g)(2) follow the capto-dative Principle. The substituent effects on the Fe-O bonds are much stronger than those on the less polar Fe-S bonds. Insight from this work may help the design of more effective catalytic processes. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The thermochemistry of organometallic complexes in solution and in the gas phase has been an area of increasing research interest. In this paper, the Fe-O and Fe-S homolytic bond dissociation energies [ΔHhomo(Fe-O)'s and ΔHhomo(Fe-S)'s] of two series of meta-substituted phenoxydicarbonyl(η5-cyclopentadienyl) iron [m-G-C6H4OFp (1)] and (meta-substituted benzenethiolato)dicarbonyl(η5-cyclopentadienyl) iron [m-G-C6H4SFp (2)] were studied using Hartree-Fock and density functional theory methods with large basis sets. In this study, Fp is (η5-C5H5)Fe(CO)2, and G are NO2, CN, COMe, CO2Me, CF3, Br, Cl, F, H, Me, MeO, and NMe2. The results show that Tao-Perdew-Staroverov-Scuseria and Minnesota 2006 functionals can provide the best price/performance ratio and accurate predictions of ΔHhomo(Fe-O)'s and ΔHhomo(Fe-S)'s. The polar effects of the meta substituents show that the dominant role to the magnitudes of ΔΔHhomo(Fe-O)'s or ΔΔHhomo(Fe-S)'s. sa·, sc· values for meta substituents are all related to polar effects. Spin-delocalization effects of the meta substituents in ΔΔHhomo(Fe-O)'s and ΔΔHhomo(Fe-S)'s are small but not necessarily zero. Molecular effects rather than ΔΔHhomo(Fe-O)'s and ΔΔHhomo(Fe-S)'s are more suitable indexes for the overall substituent effects on ΔHhomo(Fe-O)'s and ΔHhomo(Fe-S)'s. The meta substituent effects of meta-electron-withdrawing groups on the Fe-S bonds are much stronger than those on the Fe-O bonds. For meta-electron-donating groups, the meta substituent effects have the comparable magnitudes between series 1 and 2. ΔΔHhomo(Fe-O)'s (1) and ΔΔHhomo(Fe-S)'s (2) conform to the captodative principle. Insight from this work may help the design of more effective catalytic processes. [ABSTRACT FROM AUTHOR]