Sulfuric Acid → 3-Hydroxyisoquinoline

HRID 1075817Notes

Reaction equation

HRID 1075817 reaction equation
[CH:1]([NH:3][C:4](=[O:12])[CH2:5][C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][CH:7]=1)=O.S(=O)(=O)(O)O.[OH-].[NH4+]>O>[CH:1]1[NH:3][C:4](=[O:12])[CH:5]=[C:6]2[C:11]=1[CH:10]=[CH:9][CH:8]=[CH:7]2

Participants

5

Reactant 3

HCID 1118Sulfuric Acid2×HCID 14923Ammonium HydroxideHCID 3268658N-formyl-2-phenylacetamide

Product 1

HCID 27365543-HydroxyisoquinolineYield 40%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent2×

Procedure

200 g. N-formyl-2-phenyl-acetamide are dissolved in an inert atmosphere (nitrogen) in 1250 ml. concentrated sulfuric acid, while stirring and cooling in a bath of cold water in order to maintain the temperature at about 20°-25°C., whereafter the reaction mixture is left to stand for 4 hours at ambient temperature. The sulfuric acid solution is then poured, with stirring, into about 4 liters of a mixture of ice and water, the temperature not exceeding 50°C. The reaction mixture is then filtered through "Hyflo Super-Cel" a very pure diatomaceous silica filter-aid sold by Johns-Manville Sales Corp. (HYFLO is a Trade Mark). The filtrate obtained is poured, while stirring mechanically and cooling in ice (temperature of the reaction medium about 20°C.), into 3.5 liters concentrated ammonium hydroxide solution. The yellow precipitate of 2H-3-isoquinolone obtained is filtered off, washed with water and dried. There are obtained 72 g. of product; m.p. 201°C.; yield 40% of theory.

Workup

  1. temperatureto maintain the temperature at about 20°-25°C.
  2. waitwhereafter the reaction mixture is left
  3. customexceeding 50°C
  4. filtrationThe reaction mixture is then filtered through "Hyflo Super-Cel" a very pure diatomaceous silica
  5. filtrationfilter-aid
  6. customThe filtrate obtained
  7. additionis poured

Sources & evidence

ORD record
ord-c785853fc1cf44f685336f2d80aba288
Source dataset
uspto-grants-1976_05
Patent number
US03954771

Reaction notes

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