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Formation of metallacarboxylic acids through Hieber base reaction. A density functional theory study.

ABSTRACT: Using density functional theory (B97-D/ECP2/PCM//RI-BP86/ECP1 level), we have studied the effects of ligand variation on OH- uptake by transition-metal carbonyls (Hieber base reaction), i.e., LnM(CO)?+?OH-???[LnM(CO2H)]-, M?=?Fe, Ru, Os, L?=?CO, PMe3, PF3, py, bipy, Cl, H. The viability of this step depends notably on the nature of the co-ligands, and a large span of driving forces is predicted, ranging from ?G?=?-144 kJ/mol to +122 kJ/mol. Based on evaluation of atomic charges from natural population analysis, it is the ability of the co-ligands to delocalize the additional negative charge (through their ?-acidity) that is the key factor affecting the driving force for OH- uptake. Implications for the design of new catalysts for water gas shift reaction are discussed. Graphical abstract ?.

SUBMITTER: Ahmad S

PROVIDER: S-EPMC6347588 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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Formation of metallacarboxylic acids through Hieber base reaction. A density functional theory study.

Ahmad Shahbaz S Berry Elisabeth A EA Boyle Conor H CH Hudson Christopher G CG Ireland Oliver W OW Thompson Emily A EA Bühl Michael M

Journal of molecular modeling 20190125 2

Using density functional theory (B97-D/ECP2/PCM//RI-BP86/ECP1 level), we have studied the effects of ligand variation on OH- uptake by transition-metal carbonyls (Hieber base reaction), i.e., LnM(CO) + OH- → [LnM(CO2H)]-, M = Fe, Ru, Os, L = CO, PMe3, PF3, py, bipy, Cl, H. The viability of this step depends notably on the nature of the co-ligands, and a large span of driving forces is predicted, ranging from ...[more]

PMID: 30684012

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