Cobalt-catalyzed Alkoxycarbonylation of Monosubstituted Methyl Chlorides

Abstract

Synthesis of alkyl esters from monosubstituted methyl chlorides, carbon monoxide and methyl alcohol under various conditions has been studied kinetically in the presence of a catalytic amount of [Co₂(CO)₈]. By postulating a reaction scheme which could explain the experimental result satisfactorily, the rate equation has been derived as
V₀=(k₂k₃[Co]₀[RX]₀P_CO)/(k₂[RX]₀+k₃P_CO) (equation 15)
The rate constants of oxidative addition, k₂, and carbon monoxide insertion, k₃, have been determined (Table 5) and proved to be related with the Taft' σ* constants of the substituted groups.