The synthesis of deuterated methyl methacrylates

Methyl esters of: 2‐methyl [3‐2H2]prop‐2‐enoic acid (methyl methacrylate‐d2, CD2C(CH3)CO2CH3) and 2‐[Me‐2H3]methylprop‐2‐enoic acid (methyl methacrylate‐d3, CH2C(CD3)CO2CH3) were prepared in high yield under mild conditions from carbomethoxymethyltriphenylphosphonium bromide in a new application of the Wittig reaction. The methyl ester of 2‐methylprop[2H5]‐2‐enoic acid (methyl methacrylate‐d5, CD2C(CD2CH3) was prepared from acetone‐d6 via the acetone cyanohydrin method. Densities of all three monomers are reported at 25, 45 and 60°C.