Benzaldehyde → (3R,7aS)-3-Phenyltetrahydro-3H,5H-pyrrolo[1,2-c][1,3]oxazol-5-one

Participants

Reaction Steps

A suspension of 148.5 g of (S)-5-hydroxymethyl-pyrrolidin-2-one in 891 mL of toluene is treated with 172.1 mL of benzaldehyde at room temperature. p-Toluenesulphonic acid (2.94 g) is added and the reaction mixture stirred at reflux for 20 hours with azeotropic removal of water. The reaction mixture is treated with 500 mL of a 5% solution of sodium hydrogen carbonate in water. The organic layer is separated and washed once with 500 mL of a 40% solution of sodium bisulphite solution followed by 2×250 mL of water. The organic layer is dried with sodium sulphate, filtered and the solvent removed to give an oil. Fractional distillation in vacuum produces pure (3R,7aS)-3-phenyl-tetrahydro-pyrrolo[1,2-c]oxazol-5-one.

Provenance & Evidence