Ethyl thiooxamate → Ethyl 4-isopropylthiazole-2-carboxylate

Participants

Reaction Steps

1-Bromo-3-methylbutan-2-one (3.72 g) in ethanol (15 mL) was added dropwise over 15 minutes to a refluxing solution of ethyl 2-amino-2-thioxoacetate (3 g) in ethanol (120 mL). The mixture was heated at reflux for 2 hours and then cooled to room temperature. The solvent was evaporated down under reduced pressure to a volume of 30 mL, this solution was added to ice/water (200 mL) and the mixture neutralised by dropwise addition of ‘880’ concentrated aqueous ammonia. The mixture was extracted twice with ethyl acetate, the combined organics were washed with brine, dried over sodium sulphate, filtered and the solvent evaporated under reduced pressure. The crude product was purified by flash silica chromatography eluting with 20% ethyl acetate in isohexane. Pure fractions were evaporated to dryness to afford the subtitled compound. Yield 2.2 g.

Provenance & Evidence