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

HRID 1292562Notes

Reaction equation

HRID 1292562 reaction equation
[NH:1]1[CH2:6][CH2:5][NH:4][CH2:3][CH2:2]1.[C:7]([C:9]1[CH:14]=[CH:13][CH:12]=[CH:11][C:10]=1[S:15]Cl)#[N:8]>ClC1C=CC=CC=1>[N:1]1([C:7]2[C:9]3[CH:14]=[CH:13][CH:12]=[CH:11][C:10]=3[S:15][N:8]=2)[CH2:6][CH2:5][NH:4][CH2:3][CH2:2]1

Participants

4

Reactant 2

HCID 4837PiperazineHCID 110083382-cyanobenzenesulfenyl chloride

Product 1

HCID 27721443-(1-Piperazinyl)-1,2-benzisothiazole

Reagents, catalysts & solvents 1

HCID 7964ChlorobenzeneSolvent

Conditions

Temperature
130 °C

Procedure

86.2 g (1.00 mol) of piperazine and 7.5 g of chlorobenzene were placed in a 500 ml four-neck flask equipped with a stirrer, a thermometer, a dropping funnel and a condenser and 42.4 g (0.25 mol) of molten 2-cyanobenzenesulfenyl chloride was added dropwise thereto at about 130° C. over one hour while stirring, followed by stirring for four hours to complete the reaction. The excess piperazine was removed with water, followed by acidification with hydrochloric acid and extraction into the aqueous layer. The aqueous layer was basified with an aqueous sodium hydroxide solution to obtain 40.9 g (m.p.: 89°-90° C.) of 3-(1-piperazinyl)-1,2-benzisothiazole as crystals. The yield starting from 2-cyanobenzenesulfenyl chloride was 74.7%.

Workup

  1. customequipped with a stirrer
  2. stirringby stirring for four hours
  3. customthe reaction
  4. customThe excess piperazine was removed with water
  5. extractionfollowed by acidification with hydrochloric acid and extraction into the aqueous layer

Sources & evidence

ORD record
ord-32d19eed9477431cb56605f74b940ba2
Source dataset
uspto-grants-1998_05
Patent number
US05756806

Reaction notes

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