Cesium carbonate → ethyl-(R)-4-(1-carbamoylpropylamino)butyrate

Participants

Reaction Conditions

Reaction Steps

A mixture of powdered caesium carbonate (9.0 g, 27.4 mmol, 5 equiv.), ethyl-4-aminobutyrate (IVb) (1.85 g, 11.0 mmol, 2 equiv.) and methanesulfonic acid (R)-1-carbamoyl-propyl ester (IIi) (1.0 g, 5.5 mmol, 1 equiv.) in acetonitrile (20 ml, 20 vol.) is heated to 60° C. for 16 hours. The mixture is then filtered and the cake rinsed with acetonitrile (50 ml). Combined filtrates are concentrated to dryness under reducd pressure. The crude methyl-(R)-4-(1-carbamoylpropylamino)butyrate is used directly in the next step.

Provenance & Evidence