1-(2-Hydroxyethyl)piperazine → 1-(Thiophen-2-yl)piperazine

HRID 862371Notes

Reaction equation

HRID 862371 reaction equation
[S:1]1[CH:5]=[CH:4][CH:3]=[C:2]1S.OCC[N:10]1[CH2:15][CH2:14][NH:13][CH2:12][CH2:11]1.CCCCCC.C(OCC)(=O)C>C1(C)C=CC=CC=1>[N:10]1([C:2]2[S:1][CH:5]=[CH:4][CH:3]=2)[CH2:15][CH2:14][NH:13][CH2:12][CH2:11]1

Participants

6

Reactant 4

HCID 76771-(2-Hydroxyethyl)piperazineHCID 8058HexaneHCID 8857Ethyl AcetateHCID 5226742-Thiophenethiol

Product 1

HCID 219501301-(Thiophen-2-yl)piperazineYield 96.3%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

2-[1-(2'-hydroxyethyl)piperazino] thiophene 18 was prepared by warming a solution containing thiophene-2-thiol (1.16 g, 10.0 mmol.) and 1-(2-hydroxyethyl) piperazine (1.43 g, 11.0 mmol.) in toluene to reflux under an argon atmosphere for two hours. Completion of the reaction was confirmed by thin layer chromatography using a 4:1 ratio blend of hexane and ethyl acetate as the eluent. The reaction mixture was cooled to room temperature, and the solvent was removed in vacuo. The residue was then concentrated onto 5 g of silica. The silica was added to a medium pressure chromatography column packed with silica. The column was eluted with a 4:1 ratio blend of hexane and ethyl acetate to yield the pure piperazino-thiophene 18 (1.62 g, 76.4% yield) as a pale yellow solid.

Workup

  1. temperatureby warming a solution
  2. temperatureto reflux under an argon atmosphere for two hours
  3. customthe solvent was removed in vacuo
  4. concentrationThe residue was then concentrated onto 5 g of silica
  5. additionThe silica was added to a medium pressure chromatography column
  6. washThe column was eluted with a 4:1 ratio blend of hexane and ethyl acetate

Sources & evidence

ORD record
ord-472620087d7a4ab39b05be682a0d5f5c
Source dataset
uspto-grants-1998_02
Patent number
US05718845

Reaction notes

Loading…