Trifluoroacetic acid → 4-[N'-(2-methoxyphenyl)ureido]-3-methylphenylacetic acid
Reaction equation
[CH3:1][O:2][C:3]1[CH:8]=[CH:7][CH:6]=[CH:5][C:4]=1[NH:9][C:10](=[O:27])[NH:11][C:12]1[CH:17]=[CH:16][C:15]([CH2:18][C:19]([O:21]C(C)(C)C)=[O:20])=[CH:14][C:13]=1[CH3:26].FC(F)(F)C(O)=O>C(Cl)Cl>[CH3:1][O:2][C:3]1[CH:8]=[CH:7][CH:6]=[CH:5][C:4]=1[NH:9][C:10](=[O:27])[NH:11][C:12]1[CH:17]=[CH:16][C:15]([CH2:18][C:19]([OH:21])=[O:20])=[CH:14][C:13]=1[CH3:26]Participants
4
Procedure
To a stirred solution of tert-butyl 4-[N′-(2-methoxyphenyl)ureido]-3-methylphenylacetate (1.32 g, 3.56 mmol) in CH2Cl2 (15 ml) was added trifluoroacetic acid (10 ml), and the resulting mixture was heated under reflux for 30 min. The mixture was concentrated in vacuo and added water to give precipitate which was collected by filtration. The crude solid was recrystallized from EtOH/hexane to give 4-[N′-(2-methoxyphenyl)ureido]-3-methylphenylacetic acid (932 mg, 83%) as a white powder. mp 260–264° C.; 1H-NMR (CD3OD) δ 2.30 (s, 3 H), 3.55 (s, 2 H), 4.87 (s, 3 H), 6.87–6.92 (m, 2 H), 6.97–6.99 (m, 2 H), 7.10–7.24 (m, 2 H), 7.53–7.58 (m, 1 H), 8.04 (d, J=7.2 Hz, 1 H); MS (ESI) m/z 314 (M+).