Water → 7-Nitro-4-hydroxy-1,2-benzisothiazole

HRID 1449116Notes

Reaction equation

HRID 1449116 reaction equation
Cl[C:2]1[C:7]2[CH:8]=[N:9][S:10][C:6]=2[C:5]([N+:11]([O-:13])=[O:12])=[CH:4][CH:3]=1.[OH-].[Na+].O.S(=O)(=O)(O)[OH:18]>C(O)C>[N+:11]([C:5]1[C:6]2[S:10][N:9]=[CH:8][C:7]=2[C:2]([OH:18])=[CH:3][CH:4]=1)([O-:13])=[O:12]

Participants

6

Reactant 4

HCID 962WaterHCID 1118Sulfuric AcidHCID 14798Sodium HydroxideHCID 124306574-Chloro-7-nitro-1,2-benzisothiazole

Product 1

HCID 1357653737-Nitro-4-hydroxy-1,2-benzisothiazoleYield 86%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

43 g of 4-chloro-7-nitro-1,2-benzisothiazole and 16 g of sodium hydroxide powder in 400 ml of ethanol are stirred for 1 hour at 70° C. When the mixture has cooled, 500 ml of water are added, the batch is neutralized with dilute sulfuric acid whilst cooling with ice, and the product which has precipitated is filtered off. The filter cake is then washed with a little ice-cold methanol, and dried. 34 g (86% of theory) of 7-nitro-4-hydroxy-1,2-benzisothiazole are obtained, melting at 284° C. (with decomposition) after one recrystallization from n-butanol.

Workup

  1. temperatureWhen the mixture has cooled
  2. temperaturewhilst cooling with ice
  3. customthe product which has precipitated
  4. filtrationis filtered off
  5. washThe filter cake is then washed with a little ice-cold methanol
  6. customdried

Sources & evidence

ORD record
ord-1450cd4b526b4bcebb170dbd97b1982f
Source dataset
uspto-grants-1980_02
Patent number
US04189433

Reaction notes

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