Formaldehyde → diethyl (3S,4S)-1-benzylpyrrolidine-3,4-dicarboxylate

Participants

Reaction Conditions

Reaction Steps

Fumaric acid diethylester (21.6 g; 0.126 mol) is dissolved in toluene (900 ml) and heated at 105° C. A mixture of N-benzylglycine (25 g; 0.151 mol) and paraformaldehyde (25.36 g; 0.844 mol) is added in 4 g portions to the refluxing solution. After completion of the addition the mixture is heated for 18 h at 105° C. The mixture is then evaporated to dryness and suspended in n-hexane. The insoluble material is filtered off and the remaining solution is evaporated to dryness. The crude product is used for the next step without further purification. Yield: 32.5 g (70.3%), ESI-MS: m/z=306 [M+H]+

Provenance & Evidence