Water → HCID 11344558, compound

Participants

Reaction Steps

A solution of 4-methoxybenzoic acid 2,2-diethoxy-ethyl ester (2b, 7.5 g, 28 mmol) in Cl2CH2 (75 ml) was treated with TFA (16.7 g, 11.3 ml, 140 mmol) and water (7.5 g, 7.5 ml, 28 mmol). The homogeneous solution was stirred for 3.5 hours at room temperature until GC showed complete reaction. The solution was concentrated in vacuo at 40° C. and then diluted with hexane and concentrated in vacuo several times to remove traces of TFA. The product, 4-methoxybenzoic acid 2-oxo-ethyl ester (2c, 5.9 g, 28 mmol, 100%) was isolated as an amorphous white solid and was used in the next step without any further purification. GC (Rt=11.0 min, 95%); 1H-NMR (CDCl3) δ: 9.72 (1H, s, HCO—), 8.06 (2H, d, J=8.8, ArH), 6.95 (2H, d, J=8.8, ArH), 4.87 (2H, s, HCOCH2O—), 3.87 (3H, s, OCH3).

Provenance & Evidence