Piperazine → 3-(1-Piperazinyl)-1,2-benzisothiazole

HRID 1585781Notes

Reaction equation

HRID 1585781 reaction equation
[NH:1]1[CH2:6][CH2:5][NH:4][CH2:3][CH2:2]1.ClC1C=CC=CC=1.[C:14]([C:16]1[CH:21]=[CH:20][CH:19]=[CH:18][C:17]=1[S:22]Cl)#[N:15]>C(O)CO>[N:1]1([C:14]2[C:16]3[CH:21]=[CH:20][CH:19]=[CH:18][C:17]=3[S:22][N:15]=2)[CH2:6][CH2:5][NH:4][CH2:3][CH2:2]1

Participants

5

Reactant 3

HCID 4837PiperazineHCID 7964ChlorobenzeneHCID 110083382-cyanobenzenesulfenyl chloride

Product 1

HCID 27721443-(1-Piperazinyl)-1,2-benzisothiazoleYield 91%

Reagents, catalysts & solvents 1

HCID 174Ethylene GlycolSolvent

Procedure

215.4 g (2.50 mol) of piperazine, 50.0 g of chlorobenzene, 100.0 g of ethylene glycol were placed in a four-neck 1000 ml flask equipped with a stirrer, a thermometer, a dropping funnel and a condenser, 214.1 g (1.00 mol) of 2-cyanobenzenesulfenyl chloride was added dropwise in the melted state at about 120° C. over 1 hour while stirring, which was thereafter stirred for 2 hours to complete the reaction. After excess piperazine was removed with water, the reaction mixture was made acidic with hydrochloric acid, extracted into an aqueous layer, which was made alkaline with aqueous sodium hydroxide to obtain 199.5 g (m.p. 89-90° C.) of 3-(1-piperazinyl)-1,2-benzisothiazole as crystals. Yield from 2-cyanobenzenesulfenyl chloride was 91.1%.

Workup

  1. customequipped with a stirrer
  2. stirringwhich was thereafter stirred for 2 hours
  3. customthe reaction
  4. customAfter excess piperazine was removed with water
  5. extractionextracted into an aqueous layer, which

Sources & evidence

ORD record
ord-10866a8f3e92469a8bd067cb042f641b
Source dataset
uspto-grants-1999_08
Patent number
US05939548

Reaction notes

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