Water → HCID 89704884, compound

Reaction equation

[NH2:1][C:2]1[C:10]([OH:11])=[CH:9][C:5]([C:6]([OH:8])=[O:7])=[C:4]([NH:12][C:13]2[CH:18]=[CH:17][CH:16]=[CH:15][C:14]=2[F:19])[C:3]=1[F:20].[CH3:21]C1C=CC(S(O)(=O)=O)=CC=1.O>C(OC)(OC)OC>[F:20][C:3]1[C:2]2[N:1]=[CH:21][O:11][C:10]=2[CH:9]=[C:5]([C:6]([OH:8])=[O:7])[C:4]=1[NH:12][C:13]1[CH:18]=[CH:17][CH:16]=[CH:15][C:14]=1[F:19]

Participants

Procedure

To a solution of 4-amino-3-fluoro-2-((2-fluorophenyl)amino)-5-hydroxy benzoic acid (7.58 g, 27.05 mmol) in trimethyl orthoformate (50 mL) was added p-TsOH (0.23 g, 1.35 mmol). The reaction mixture was stirred for 1 h and treated with water (200 mL). The precipitate was filtered off and the filter cake was washed with water to afford the desired product (7.22 g, 82.7% yield for two steps). 1H NMR (400 MHz, CDCl3): δ 8.28 (s, 1H), 8.27 (s, 1H), 8.24 (s, 1H), 7.14 (m, 1H), 7.05 (m, 2H), 6.86 (m, 1H).