Ammonium formate → Ethyl 4-ethyloxazole-5-carboxylate

Beteiligte Stoffe

Reaktionsschritte

2-Chloro-3-oxo-pentanoic acid ethyl ester (13.5 g) was dissolved in 75 ml of 95% formic acid. Ammonium formate (27.6 g) was added and the reaction heated at reflux under nitrogen for 6 hours. After cooling to room temperature the reaction mixture was evaporated and the residue extracted with ether (3×50 ml). Combined ether extracts were washed with water and brine, dried (MgSO4), filtered and evaporated to give a crude oil (9 g). The oil was purified by chromatography on silica gel, eluting with CH2Cl2/MeOH 99:1, providing the title compound (3.77 g) as a pale brown oil.

Herkunft & Nachweise