Phosphoric Acid → HCID 57294103, compound

Participants

Reaction Steps

A mixture of 2-pentanone (17.1 g, 198 mmol), glyoxylic acid monohydrate (8.05 g, 88 mmol) and about 85% phosphoric acid (12 ml) was warmed at ca. 80° for 19 hours. On cooling to room temperature the mixture was diluted with ethyl ether/dichloromethane (100 ml, 1:1) and washed thoroughly with brine. Evaporation of the dried (magnesium sulphate) organic phase gave a yellow viscous oil, which on crystallization from ethyl ether/petroleum ether gave 4-keto-hept-2-enoic acid as colorless prisms: mp 100°-2°.

Provenance & Evidence