Acetate → 4-(N-methylacetamido)benzoic acid

Participants

Reaction Steps

To a solution of N-methyl-4-aminobenzoic acid (2.0 g, 13.2 mmol) in anhydrous pyridine (13.2 mL) was added acetic anhydride (1.4 mL, 14.5 mmol). The reaction was stirred at ambient temperature until TLC indicatedcomplete reaction (~22 hours). The resultant solution was poured intoethyl acetate and the organic phase was washed (3×, 10% HCl; 1×, water; 1×, brine), dried (MgSO4), filtered and concentrated in vacuo to provide the amide as a colorless solid. Recrystallization (ethyl acetate/hexane) afforded 4-(N-acetyl-N-methylamino)benzoic acid (2.15 g, 84.0%). 1H NMR (300 MHz, CDCl3) d 8.18 (2H, br d, J=8.5 Hz), 7.33 (2H, br d, J=8.5 Hz), 3.33 (3H, s), 2.0 (3H, br s). MS m/e 194 (M+H)+, 211 (M+NH4)+.

Provenance & Evidence