Reaction of potassium tetracarbonylhydridoferrate with aryl halides: Mechanistic study and extension to the catalytic carbonylation of iodobenzene by a bimetallic Fe(CO) sub 5 -Co sub 2 (CO) sub 8 system

Journal Article · Tue Jan 01 04:00:00 EST 1991 · Organometallics; (United States)

DOI:https://doi.org/10.1021/om00047a070· OSTI ID:6106709

Brunet, J J; de Montauzon, D; Taillefer, M ^[1]

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1. Centre National de la Recherche Scientifique, Toulouse (France)

Potassium tetracarbonylhydridoferrate, KHFe(CO){sub 4}, reacts with aryl iodides in wet methanol to yield the corresponding arenes. This reaction is catalytic under carbon monoxide (1 atm) in the presence of an excess of base. Mechanistic investigations, both by IR analysis and by electrochemical experiments, show that the reaction involves an electron transfer from HFe(CO){sub 4}{sup {minus}} to the aryl halide to generate the corresponding radical anion. The resulting aryl radical either abstracts an hydrogen atom from potassium methoxide or combines with the (HFe(CO){sub 4}){sup {sm bullet}} radical species to form ArFe(H)(CO){sub 4}, which yields ArH by reductive elimination. The catalytic carbonylation of iodobenzene to benzoic acid can be performed under very mild conditions by a bimetallic system, viz. HFe(CO){sub 4}{sup {minus}}-Co(CO){sub 4}{sup {minus}}. The observed synergetic effect is believed to involve first an electron transfer from HFe(CO){sub 4}{sup {minus}} to iodobenzene and generation of a phenyl radical, followed by reaction with Co(CO){sub 4}{sup {minus}}, which acts as the actual carbonylation catalyst. In agreement with these hypotheses, the carbonylation of bromobenzene, which on its own is unreactive under these conditions, can be promoted by the presence of iodobenzene.

• OSTI ID: 6106709
• Journal Information: Organometallics; (United States), Journal Name: Organometallics; (United States) Vol. 10:1; ISSN 0276-7333; ISSN ORGND
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CARBONYLATION
CATALYTIC EFFECTS
CHALCOGENIDES
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
COBALT COMPLEXES
COMPLEXES
DECOMPOSITION
ELECTRON TRANSFER
INFRARED SPECTRA
IRON COMPLEXES
KINETICS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC IODINE COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
REACTION INTERMEDIATES
REACTION KINETICS
SPECTRA
TRANSITION ELEMENT COMPLEXES