Sulfuric Acid → 2,3,5,6-Tetrafluoroaniline

HRID 1060343Notes

Reaction equation

HRID 1060343 reaction equation
S(=O)(=O)(O)O.[NH2:6][C:7]1[C:14]([F:15])=[C:13]([F:16])[C:10](C#N)=[C:9]([F:17])[C:8]=1[F:18].NC1C(F)=C(F)C(F)=C(F)C=1C#N>>[F:15][C:14]1[C:13]([F:16])=[CH:10][C:9]([F:17])=[C:8]([F:18])[C:7]=1[NH2:6]

Participants

4

Conditions

Temperature
140 °C

Procedure

2,3,5,6-Tetrafluoroaniline was produced from 4-amino-2,3,5,6-tetrafluorobenzonitrile. To be specific, in a 200 ml four-neck flask provided with a stirrer, a thermometer, a dropping funnel, and a water separating tube, 100 g of 60% sulfuric acid was placed and heated to 140° C. To the hot sulfuric acid, 36 g of the raw material, 4-amino-2,3,5,6-tetrafluorobenzonitrile (having a purity of 94% and containing 6% of 2-amino-3,4,5,6-tetrafluorobenzonitrile as an impurity) was added dropwise at a rate of 6 g/hr. The 2,3,5,6-tetrafluoroaniline which was formed by the reaction was expelled by azeotropy with water, guided into the water dropping tube, and separated from the water. The reaction was continued for six hours while the reaction vessel was supplied with the same amount of water as expelled by distillation. After the completion of the reaction, the conversion ratio of the raw material determined by gas chromatography was found to be 96 mol %. When the 2,3,5,6-tetrafluoroaniline expelled by distillation was analyzed, the purity was found to be 95.3% and the yield to be 82.5%.

Workup

  1. customTo be specific, in a 200 ml four-neck flask
  2. customprovided with a stirrer
  3. additionwas added dropwise at a rate of 6 g/hr

Sources & evidence

ORD record
ord-c82e6f67570b4988be1a3777a2109457
Source dataset
uspto-grants-2003_02
Patent number
US06521794B2

Reaction notes

Loading…