Sodium Hydroxide → HCID 19083162, compound

HRID 1734416Notes

Reaction equation

HRID 1734416 reaction equation
[NH2:1]OS(O)(=O)=O.[OH-].[Na+].[CH3:9][N:10]1[C:18]([S:19]([O-:21])=[O:20])=[C:17]2[C:12]([CH:13]=[CH:14][CH:15]=[CH:16]2)=[N:11]1.[Li+]>O>[CH3:9][N:10]1[C:18]([S:19]([NH2:1])(=[O:21])=[O:20])=[C:17]2[C:12]([CH:13]=[CH:14][CH:15]=[CH:16]2)=[N:11]1

Participants

5

Reactant 3

HCID 14798Sodium HydroxideHCID 76284hydroxylamine-O-sulfonic acidHCID 23675697HCID 23675697, compound

Product 1

HCID 19083162HCID 19083162, compoundYield 58%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent2×

Conditions

Temperature
10 °C

Procedure

A solution containing 9.5 g (72 mmol) of 2-methyl-2H-indazole in 200 ml of ethyl ether, was cooled to -30° C., and 61.4 g (144 mmol) of n-butyl lithium (a 15% hexane solution) was dropwise added thereto. The mixture was stirred for one hour at the same temperature, and then an excess amount of sulfurous acid gas was blown thereinto for 3 hours at a temperature of not higher than -20° C. After completion of the reaction, the mixture was returned to room temperature, stirred for 12 hours and then diluted with ethyl ether. The product was subjected to filtration. The crystals were dried to obtain crude lithium 2-methyl-2H-indazole-3-sulfinate. This product was used for the subsequent reaction without purification. 48.8 g (430 mmol) of hydroxylamine-O-sulfonic acid was gradually added to a solution containing 17.2 g (430 mmol) of sodium hydroxide in water 300 ml) under cooling with ice (not higher than 10° C.). This solution was added all at once to a solution containing the crude lithium 2-methyl-2H-indazole-3-sulfinate previously prepared in water (100 ml), and then the mixture was stirred for 12 hours at room temperature. Formed crystals were collected by filtration to obtain 8.8 g (yield: 58%) of 2-methyl-2H-indazole-3-sulfonamide (slightly yellow granular crystals). Melting point: 181°-183° C.

Workup

  1. customThis product was used for the subsequent reaction without purification
  2. additionThis solution was added all at once to a solution
  3. customFormed crystals
  4. filtrationwere collected by filtration

Sources & evidence

ORD record
ord-830665711a7d43ee9a0ca80fe6f16f31
Source dataset
uspto-grants-1996_07
Patent number
US05534481

Reaction notes

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