1,2-Dichloroethane → 3-Nitro-4-(trifluoromethyl)benzoic acid

HRID 257574

反応式

HRID 257574 の反応式
[N+:1]([C:4]1[CH:9]=[C:8](C)[CH:7]=[CH:6][C:5]=1[C:11]([F:14])([F:13])[F:12])([O-:3])=[O:2].ClCCCl.Cl[O-].[Na+].[OH-].[Na+].[C:24]([O-:27])(O)=[O:25].[Na+]>[Br-].C([N+](CCCC)(CCCC)CCCC)CCC.O.[Ru](Cl)(Cl)Cl>[N+:1]([C:4]1[CH:9]=[C:8]([CH:7]=[CH:6][C:5]=1[C:11]([F:12])([F:13])[F:14])[C:24]([OH:27])=[O:25])([O-:3])=[O:2]

参加物

8

反応物 5

HCID 111,2-DichloroethaneHCID 14798Sodium Hydroxide2 回HCID 516892Sodium BicarbonateHCID 197831564-Methyl-2-nitro-1-(trifluoromethyl)benzeneHCID 23665760Sodium Hypochlorite3 回

生成物 1

HCID 27790153-Nitro-4-(trifluoromethyl)benzoic acid収率 49%

試薬・触媒・溶媒 2

HCID 74236Tetrabutylammonium Bromide触媒HCID 6093376Ruthenium trichloride hydrate触媒

反応条件

温度
45 °C

実験手順

To a rapidly stirred mixture of 1.00 g (4.88 mmol) of 2-nitro-4-methylbenzotrifluoride (from Step A), 236 mg (0.732 mmol) of tetra-n-butylammonium bromide, 51 mg (0.244 mmol) of ruthenium trichloride hydrate, and 2 mL of 1,2-dichloroethane were added five 5.8 -mL (approximately 22 mmol) portions of 13% sodium hypochlorite solution (aqueous, approx. 3.8M) while monitoring and adjusting the pH. With each addition of sodium hypochlorite solution, 5N NaOH was added as necessary to maintain the pH between 8.5 and 10.5, and the next portion of sodium hypochlorite was added only when the pH was stable for about 5 minutes. The entire addition required approximately 2 hours, and the final pH was 10.3. After being stirred overnight at 45° C., the 2-phase mixture was cooled and separated. The aqueous phase was acidified to pH 3 by addition of 20% sulfuric acid and extracted 3× with ethyl acetate. The combined organic extracts were washed with H2O (3×), then with brine, and dried over anhydrous Na2SO4. The residue obtained upon concentration was taken up in 5% NaHCO3 (aqueous) adjusted to pH 9 with 5% NaOH. The aqueous phase was washed twice with methylene chloride and then with ether. Next, the water phase was acidified with 20% sulfuric acid and extracted with ethyl acetate as above to yield 563 mg (49%) of the title compound as an off-white solid, mp 156°-158° C.; TLC in 1:1 hexane-EtOAc (at origin); mass spectrum (EI) m/e 235 (M+). 200 MHz 1H NMR (CD3OD) δ7.87 (d, J=8 Hz, 1H), 8.31 (d, J=8 Hz, 1H), 8.45 (s, 1H).

後処理

  1. additionwas added as necessary
  2. temperatureto maintain the pH between 8.5 and 10.5
  3. additionThe entire addition required approximately 2 hours
  4. temperaturethe 2-phase mixture was cooled
  5. customseparated
  6. additionThe aqueous phase was acidified to pH 3 by addition of 20% sulfuric acid
  7. extractionextracted 3× with ethyl acetate
  8. washThe combined organic extracts were washed with H2O (3×)
  9. dry with materialwith brine, and dried over anhydrous Na2SO4
  10. customThe residue obtained upon concentration
  11. washThe aqueous phase was washed twice with methylene chloride
  12. extractionextracted with ethyl acetate as above

出典と根拠

ORDレコード
ord-68c384858fbc45a39c79ce8447993645
出典データセット
uspto-grants-1993_11
特許番号
US05262412

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