Hydrochloric Acid → Benzoic acid, 4-amino-2,3-difluoro-5-nitro-, methyl ester

HRID 992386Notes

Reaction equation

HRID 992386 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

5

Reactant 4

HCID 313Hydrochloric AcidHCID 887MethanolHCID 253877Potassium BromideHCID 162440884-Amino-2,3-difluoro-5-nitrobenzoic acid

Product 1

HCID 2759749Benzoic acid, 4-amino-2,3-difluoro-5-nitro-, methyl esterYield 70%

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) δ8.36 (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

  1. temperaturewas warm
  2. temperatureto reflux
  3. temperatureto cool slowly on the bench
  4. customA yellow precipitate formed
  5. filtrationwas collected by vacuum filtration
  6. customdried with suction
  7. customto afford 0.35 g of yellow microfilaments

Sources & evidence

ORD record
ord-c1972f020a77407aa42e1e28bc26b880
Source dataset
uspto-grants-2002_10
Patent number
US06469004B1

Reaction notes

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