General procedure for the synthesis of 2-hydroxymethyl oxazole from oxazole-2-carboxaldehyde: To a methanol (25 mL) solution of oxazole-2-carboxaldehyde (90 mg, 9.28 mmol) was slowly added sodium borohydride (420 mg, 11.14 mmol) at 0 °C. The reaction mixture was gradually warmed to room temperature and stirred continuously for 1 hour. Upon completion of the reaction, the reaction was quenched by the addition of water (25 mL), and the organic phase was extracted with ethyl acetate, followed by washing with saturated brine solution (50 mL), drying with anhydrous sodium sulfate, filtration, and concentration to afford the crude product, 2-hydroxymethyl oxazole. The crude product was purified by column chromatography (silica gel 100-200 mesh, eluent 50% ethyl acetate/petroleum ether) to give purified 2-hydroxymethoxazole (160 mg, 14% yield) as a colorless liquid. Thin layer chromatography (TLC) Rf value was 0.4 (50% ethyl acetate/petroleum ether).1H-NMR (400 MHz, CDCl3): δ 7.64 (s, 1H), 7.09 (s, 1H), 4.75 (s, 2H). Mass spectrum (m/z, APCI positive ion mode): 100.3 ([M+H]+).
