Synthesis of Tetramethyl 2,6‐Dihydroxybicyclo[3.3.1]nona‐2,6‐diene‐1,3,5,7‐tetracarboxylate (Meerwein Ester). – Use of tert‐Butyl Methyl Ether Instead of Benzene in Azeotropic Distillation

In the condensation of dimethyl malonate with formaldehyde, leading eventually to the title compound 5, water is formed which is removed by azeotropic distillation with benzene in the original procedure. It is shown that benzene may be replaced by tert‐butyl methyl ether without any loss in the yield.