Piperazine → 1-(4-Bromobenzene-1-sulfonyl)piperazine

HRID 427446Notes

Reaction equation

HRID 427446 reaction equation
[NH:1]1[CH2:6][CH2:5][NH:4][CH2:3][CH2:2]1.[Br:7][C:8]1[CH:13]=[CH:12][C:11]([S:14](Cl)(=[O:16])=[O:15])=[CH:10][CH:9]=1>ClCCl.C(N(CC)CC)C>[Br:7][C:8]1[CH:13]=[CH:12][C:11]([S:14]([N:1]2[CH2:6][CH2:5][NH:4][CH2:3][CH2:2]2)(=[O:16])=[O:15])=[CH:10][CH:9]=1

Participants

5

Reactant 2

HCID 4837PiperazineHCID 7396p-Bromobenzenesulfonyl chloride

Product 1

HCID 7129241-(4-Bromobenzene-1-sulfonyl)piperazineYield 73.8%

Reagents, catalysts & solvents 2

HCID 6344DichloromethaneSolvent2×HCID 8471TriethylamineSolvent

Procedure

To a stirred solution of piperazine (10.8 g) in dry dichloromethane (160 ml) and triethylamine (20 ml) at 0° C. was added slowly a solution of 4-bromobenzenesulphonyl chloride (16 g) in dichloromethane (80 ml) and stirred for 24 hours. The reaction was then quenched by removal of the dichloromethane solvent by evaporation, taken up in water and extracted with ethyl acetate. The organic extracts were washed with aqueous sodium hydrogen carbonate solution, water, brine, dried (MgSO4) and then evaporated to give a white crystalline solid which was recrystallised from ethyl acetate/isohexane to afford 1-(4-bromophenylsulphonyl)piperazine (14.1 g) as a solid, m.p. 102-104° C.; microanalysis found: C, 39.5; H, 4.4; N, 9.1%: C10H13BrN2O2S requires: C, 39.4; H, 4.3; N, 9.2%; NMR (CDCl3): 1.52(s,1H), 2.97(dt,8H), 7.61(d,2H), 7.69(d,2H): MS m/z 305 (MH)+.

Workup

  1. customThe reaction was then quenched by removal of the dichloromethane solvent by evaporation
  2. extractionextracted with ethyl acetate
  3. washThe organic extracts were washed with aqueous sodium hydrogen carbonate solution, water, brine
  4. dry with materialdried (MgSO4)
  5. customevaporated
  6. customto give a white crystalline solid which
  7. customwas recrystallised from ethyl acetate/isohexane

Sources & evidence

ORD record
ord-d3d7cb9faf76409f910b016aff46b5a3
Source dataset
uspto-grants-2001_11
Patent number
US06313127B1

Reaction notes

Loading…