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

HRID 1585780Notes

Reaction equation

HRID 1585780 reaction equation
[NH:1]1[CH2:6][CH2:5][NH:4][CH2:3][CH2:2]1.ClC1C=CC=CC=1.Cl[C:15]1[C:19]2[CH:20]=[CH:21][CH:22]=[CH:23][C:18]=2[S:17][N:16]=1>C(O)CO>[N:1]1([C:15]2[C:19]3[CH:20]=[CH:21][CH:22]=[CH:23][C:18]=3[S:17][N:16]=2)[CH2:6][CH2:5][NH:4][CH2:3][CH2:2]1

Participants

5

Reactant 3

HCID 4837PiperazineHCID 7964ChlorobenzeneHCID 5981903-Chloro-1,2-benzisothiazole

Product 1

HCID 27721443-(1-Piperazinyl)-1,2-benzisothiazoleYield 92.3%

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, 169.5 g (1.00 mol) of 3-chloro-1,2-benzisothiazole 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 202.4 g (m.p. 89-90° C.) of 3-(1-piperazinyl)-1,2-benzisothiazole as crystals. Yield from 3-chloro-1,2-benzisothiazole was 92.4%.

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-57471990a9434be2b4611c35a3f241fa
Source dataset
uspto-grants-1999_08
Patent number
US05939548

Reaction notes

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