Benzeneethanol, 4-hydroxy-3-[2-(2-nitrophenyl)diazenyl]- → Benzeneethanol, 3-(2H-benzotriazol-2-yl)-4-hydroxy-

HRID 582274Notes

Reaction equation

HRID 582274 reaction equation
[OH:1][CH2:2][CH2:3][C:4]1[CH:9]=[CH:8][C:7]([OH:10])=[C:6]([N:11]=[N:12][C:13]2[CH:18]=[CH:17][CH:16]=[CH:15][C:14]=2[N+:19]([O-])=O)[CH:5]=1>[OH-].[Na+].[Zn]>[N:12]1[N:11]([C:6]2[CH:5]=[C:4]([CH2:3][CH2:2][OH:1])[CH:9]=[CH:8][C:7]=2[OH:10])[N:19]=[C:14]2[CH:15]=[CH:16][CH:17]=[CH:18][C:13]=12

Participants

4

Reactant 1

HCID 136056797Benzeneethanol, 4-hydroxy-3-[2-(2-nitrophenyl)diazenyl]-

Product 1

HCID 688251Benzeneethanol, 3-(2H-benzotriazol-2-yl)-4-hydroxy-Yield 80.5%

Reagents, catalysts & solvents 2

HCID 23994ZincCatalystHCID 14798Sodium HydroxideSolvent2×

Conditions

Temperature
70 °C

Procedure

5.39 g (18 mmols) of crude 4-(2-hydroxyethyl)-2-[(2-nitrophenyl)azo]phenol synthesized in Example 3 was dissolved in 18 ml of aqueous solution of 2N sodium hydroxide. Subsequently, 9 ml of previously prepared aqueous solution of 25% sodium hydroxide and 5.4 g (83 mmols) of zinc powder were simultaneously added over a period of about 3 hours. The reaction mixture was heated to 70° C. and stirred for about 2 hours. The reaction mixture was then cooled to room temperature and filtered to collect inorganic substance. The obtained mother liquor was acidified with concentrated hydrochloric acid. Precipitated crystals were collected by filtration and recrystalized in toluene, giving 3.70 g of 2-(2H-benzotriazole-2-yl)-4-(2-hydroxyethyl)phenol as yellow crystals (yield 70%, purity 87%).

Workup

  1. temperatureThe reaction mixture was then cooled to room temperature
  2. filtrationfiltered
  3. customto collect inorganic substance
  4. customPrecipitated crystals
  5. filtrationwere collected by filtration
  6. customrecrystalized in toluene

Sources & evidence

ORD record
ord-3e1b888676ba4ed9baa5fe80aac02c4a
Source dataset
uspto-grants-1999_07
Patent number
US05922882

Reaction notes

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