Disodium tetracarbonylferrate (–II) is an efficient catalyst for the dismutation of aromatic aldehydes to esters, 2RCHO→ RCOOCH 2 R. Aliphatic ones give aldol-condensation products upon treatment with the ferrate. A successive reaction of the ferrate with an aldehyde, RCHO, and then with alkyl iodide, R'I, gives an ester, R'COOCH 2 R, after protonation. The mechanisms of these reactions are discussed.