Kinetics and mechanism of substitution of olefinic ligands by carbon monoxide in tetracarbonyl-π-olefiniron complexes
Abstract
The mechanism of the reaction Fe(CO)4(CH2CHX)+ CO → Fe(CO)5+ CH2CHX (X = OEt, Bu, Ph, CO2Me, and CN) has been studied in toluene. The reaction mode has been found to be dissociative with intermediate formation of Fe(CO)4; an appreciable mass law retardation effect of the olefinic ligand has been found. The thermal stability of the olefinic complexes is correlated with the electron-withdrawing power of the substituent X. The relative order of thermodynamic stability of the complexes has been deduced from the mass law retardation effects of the olefinic ligands.