Penicillamine → 2,5,5-Trimethyl-2-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-1,3-thiazolidine-4-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

To a solution of 3.6 g (50 mmoles) of pyrrolidine in 50 mg of anhydrous benzene was added dropwise a solution of 4.2 g (50 mmoles) of diketene in 50 ml of anhydrous benzene at 0°-5° C. over 2 hours. The mixture was allowed to stand at room temperature for 2 hours, and the solvent was distilled off to a half its volume under reduced pressure. To the residue was added 5 g (34 mmoles) of D-penicillamine. The mixture was heated at 80° C. with stirring under a stream of argon for an hour to obtain a pale yellow and clear reaction mixture. The reaction mixture was filtered, the solvent was distilled off and the resulting residue was washed with a mixture of n-hexane and ether. The viscous residue thus obtained was crystallized from hot benzene and further recrystallized from benzene to give 9.5 g of 4-carboxy-2,5,5-trimethylthiazolidine-2-acetopyrrolidide as colorless prisms.

Provenance & Evidence