High activity cobalt based catalysts for the carbonylation of methanol

[Cp*Co(CO)2] in the presence of PEt3 and MeI catalyses the carbonylation of methanol with initial rates up to 44 mol dm–3 h–1 before decaying to a second catalytic phase with rates of 3 mol dm–3 h–1; [CoI(CO)2(PEt3)2], which is trigonal bipyramidal with axial PEt3 ligands, has been isolated from the final reaction solution.