Hydrochloric Acid → 2-(5-Chlorothiophen-2-yl)-2-oxoacetic acid

Participants

Reaction Steps

(5-Chlorothiophen-2-yl)-oxo-acetic acid ethyl ester (8.62 g, 39.4 mmol) was dissolved in a mixture of 100 ml water and 100 ml methanol, then treated with 10 N NaOH (5.9 ml, 59 mmol) at room temperature for 20 hours. The reaction was then poured into 200 ml 3N HCl, and extracted with ethyl acetate (2×100 ml). The combined ethyl acetate extracts were dried over Na2SO4 and concentrated under vacuum to provide Preparation 1b (6.89 g, 92%). The product was then recrystallized from hexane/ether. MS (M−H)−: 189.10; 1H NMR (300 MHz, CDCl3) δ9.07 (1H, br s), 8.32 (1H, d, J=4.2 Hz), 7.10 (1H, d, J=4.2 Hz). IR (KBr) 3270, 3099, 1765, 1744, 1675, 1514, 1411, 1325 cm−1.

Provenance & Evidence