Hydrogen Bromide → 3-(1-Piperazinyl)-1,2-benzisothiazole dihydrobromide

HRID 2051010Notes

Reaction equation

HRID 2051010 reaction equation
[S:1]1[C:5]2[CH:6]=[CH:7][CH:8]=[CH:9][C:4]=2[C:3]([N:10]2[CH2:15][CH2:14][N:13](C(OCC)=O)[CH2:12][CH2:11]2)=[N:2]1.[BrH:21]>O>[BrH:21].[BrH:21].[N:10]1([C:3]2[C:4]3[CH:9]=[CH:8][CH:7]=[CH:6][C:5]=3[S:1][N:2]=2)[CH2:15][CH2:14][NH:13][CH2:12][CH2:11]1

Participants

4

Reactant 2

HCID 260Hydrogen BromideHCID 15057450Ethyl 4-(1,2-benzisothiazol-3-yl)-1-piperazinecarboxylate

Product 1

HCID 198344793-(1-Piperazinyl)-1,2-benzisothiazole dihydrobromideYield 73%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

A mixture of 12.5 parts of ethyl 4-(1,2-benzisothiazol-3-yl)-1-piperazinecarboxylate and 187.5 parts of a hydrobromic acid solution 48% in water was stirred for 1.5 hours at reflux temperature. After evaporation, the residue was taken up in 2-propanol and the solvent was evaporated again. The residue was dissolved in methanol, evaporated again and stirred in 2-propanone. The product was filtered off and dried, yielding 11.5 parts (73%) of 3-(1-piperazinyl)-1,2-benzisothiazole dihydrobromide (int. 4).

Workup

  1. temperatureat reflux temperature
  2. customAfter evaporation
  3. customthe solvent was evaporated again
  4. dissolutionThe residue was dissolved in methanol
  5. customevaporated again
  6. stirringstirred in 2-propanone
  7. filtrationThe product was filtered off
  8. customdried

Sources & evidence

ORD record
ord-b17001f0e8534e728963a789e2327987
Source dataset
uspto-grants-1991_05
Patent number
US05015740

Reaction notes

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