Hydrochloric Acid → Ethyl 2-chlorothiazole-4-carboxylate

Participants

Reaction Steps

The free based 2-amino-thiazole-4-carboxylic acid ethyl ester (306 mg, 1.78 mmol) and CuCl (238 mg, 2.4 mmol) were suspended in conc. HCl (8 ml) and the mixture cooled on a salt/ice bath. A pre-cooled solution of NaNO2 (166 mg, 2.4 mmol) in water (2 ml) was added over a period of 10 min. The mixture was allowed to warm to room temperature over 1 h and was stirred for a further 1 h. Water was added and the aqueous layer extracted with EtOAc (3×10 ml). The combined EtOAc layers were washed with brine, dried (Na2SO4), filtered and the solvent removed in vacuo to give the title compound.

Provenance & Evidence