Hydrochloric Acid → Benzoic acid, 4-amino-2,3-difluoro-5-nitro-, methyl ester
Reaction equation
Cl.[NH2:2][C:3]1[C:11]([N+:12]([O-:14])=[O:13])=[CH:10][C:6]([C:7]([OH:9])=[O:8])=[C:5]([F:15])[C:4]=1[F:16].[K+].[Br-].[CH3:19]O>>[NH2:2][C:3]1[C:11]([N+:12]([O-:14])=[O:13])=[CH:10][C:6]([C:7]([O:9][CH3:19])=[O:8])=[C:5]([F:15])[C:4]=1[F:16]Participants
Procedure
Hydrogen chloride gas was dissolved in anhydrous methanol (30 ml) until the solution was warm. The solid 4-amino-2,3-difluoro-5-nitrobenzoic acid (0.47 g; 0.00215 mol) was dissolved in this solution and the reaction mixture was brought to reflux with vigorous stirring for 23 hours under a nitrogen atmosphere. The reaction mixture was allowed to cool slowly on the bench. A yellow precipitate formed and was collected by vacuum filtration and dried with suction to afford 0.35 g of yellow microfilaments; 70% yield; m.p. 183.5–184° C.; 1H-NMR (400 MHz; DMSO) δ 8.36 (dd, 1H, J=7.3, 1.7 Hz), 8.06 (s, 2H), 3.78 (s, 3H); 19F-NMR (376 MHz; DMSO) δ −128.85 to −128.92 (m), −153.29 (d); MS (APCl−) 231 (M−1, 100); IR (KBr) 3433, 3322, 1700, 1650, 1549, 1343, 1285 cm−1; Anal. calcd/found for: C8H6F2N2O4 C, 41.39/41.40; H, 2.61/2.50; N, 12.07/11.98; F, 16.37/16.58.
Workup
- temperaturewas warm
- temperatureto reflux
- temperatureto cool slowly on the bench
- customA yellow precipitate formed
- filtrationwas collected by vacuum filtration
- customdried with suction
- customto afford 0.35 g of yellow microfilaments
Sources & evidence
- ORD record
- ord-d5ae9cb39ad941b8a504db9c3791ac17
- Source dataset
- uspto-grants-2006_04
- Patent number
- US07030119B1
Reaction notes
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