Glyoxylic Acid → HCID 86737262, compound

Participants

Reaction Steps

To a slurry of 16.0 g. of p-bromopropiophenone and 8.0 g. of glyoxylic acid in 90 ml. of water is added (with cooling) a mixture of 20 g. of 50% sodium hydroxide in 280 ml. of ethanol-water (1:1). The mixture is allowed to stand at room temperature for 20 hours and then heated to the boiling point for 30 minutes. The mixture is diluted with 800 ml. of ice and water, stirred several minutes and filtered. The filtrate is acidified with 5 N HCl and filtered to give 12.5 g. of β-(4-bromobenzoyl)crotonic acid as tan crystals, m.p. 137°-144° C. The preceding compound (5.0 g.) is coupled with L-proline with N,N-carbonyldiimidazole in tetrahydrofuran to give 1-[β-(4-bromobenzoyl)crotonyl]-L-proline. A mixture of the preceding compound with thiolacetic acid in acetonitrile gives the product of the example as a glass.

Provenance & Evidence