4'-Methoxyacetophenone → Benzenepropanoic acid, 4-methoxy-beta-oxo-, ethyl ester

Participants

Reaction Conditions

Reaction Steps

To potassium t-amylate (25 wt %, 50.8 kg, 99.26 mol) in toluene (15.2 kg) cooled to 5° C. under mechanical stirring and under nitrogen was added a mixture of 4-methoxyacetophenone (6.755 kg, 44.98 mol) and diethyl carbonate (6.40 kg, 54.18 mol) in toluene over 1 hour maintaining the temperature below 10° C. The reaction mixture was heated to 60° C. for 8 hours until no 4-methoxyacetophenone was detected by HPLC. The mixture was cooled to 20° C. and quenched by adding to a mixture of acetic acid (8 kg) and water (90 kg) over 30 minutes while maintaining the temperature at <20° C. The layers were separated, and the organic layer was washed with 5% sodium bicarbonate solution (41 kg) and concentrated to 14.65 kg. The temperature is maintained below 50° C. during the distillation. The yellow product concentrate was assayed by HPLC against an external standard and the yield was found to be 9.40 kg (94%).

Provenance & Evidence