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DFT Study on the Mechanism of Iron-Catalyzed Diazocarbonylation.

ABSTRACT: The mechanism of the carbonylation of diazomethane in the presence of iron-carbonyl-phosphine catalysts has been investigated by means of DFT calculations at the M06/def-TZVP//B97D3/def2-TZVP level of theory, in combination with the SMD solvation method. The reaction rate is determined by the formation of the coordinatively unsaturated doublet-state Fe(CO)₃(P) precursor followed by the diazoalkane coordination and the N₂ extrusion. The free energy of activation is predicted to be 18.5 and 28.2 kcal/mol for the PF₃ and PPh₃ containing systems, respectively. Thus, in the presence of less basic P-donor ligands with stronger ?-acceptor properties, a significant increase in the reaction rate can be expected. According to energy decomposition analysis combined with natural orbitals of chemical valence (EDA-NOCV) calculations, diazomethane in the Fe(CO)₃(phosphine)(?¹-CH₂N₂) adduct reveals a ?-donor-?-acceptor type of coordination.

SUBMITTER: Kegl TR

PROVIDER: S-EPMC7763840 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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DFT Study on the Mechanism of Iron-Catalyzed Diazocarbonylation.

Kégl Tímea R TR Kollár László L Kégl Tamás T

Molecules (Basel, Switzerland) 20201211 24

The mechanism of the carbonylation of diazomethane in the presence of iron-carbonyl-phosphine catalysts has been investigated by means of DFT calculations at the M06/def-TZVP//B97D3/def2-TZVP level of theory, in combination with the SMD solvation method. The reaction rate is determined by the formation of the coordinatively unsaturated doublet-state Fe(CO)<sub>3</sub>(P) precursor followed by the diazoalkane coordination and the N<sub>2</sub> extrusion. The free energy of activation is predicted ...[more]

PMID: 33322410

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