A convenient and inexpensive synthesis of labelled methylmalonic and propionic acids: Application to the synthesis of methyl-d(3)-malonic and of propionic-3,3,3-d(3) acids

A synthetic route for obtaining highly pure methylmalonic and propionic acids labelled at the methyl groups is validated by the preparation of methyl-d(3)-malonic and propionic 3,3,3-d(3) acids. The synthesis involves the alkylation of the diethyl allylmalonate with iodomethane-d(3), deallylation of the resulting diethyl allylmethyl-d(3)-malonate by treatment with (eta(2)-propene)Ti(O-i-Pr)(2) and hydrolysis. Decarboxylation of the obtained methyl-d(3)-malonic acid affords propionic-3,3,3-d(3) acid