Diisopropylethylamine → 3-Bromo-1-(4-chlorophenyl)piperazine 2,2-dimethylpropan-1-one

HRID 417988

Reaction equation

HRID 417988 reaction equation
[Br:1][CH2:2][C:3]([CH3:8])([CH3:7])[C:4](O)=[O:5].Cl.Cl.[Cl:11][C:12]1[CH:17]=[CH:16][C:15]([N:18]2[CH2:23][CH2:22][NH:21][CH2:20][CH2:19]2)=[CH:14][CH:13]=1.CCN(C(C)C)C(C)C>S(Cl)(Cl)=O.CN(C=O)C.C(Cl)Cl>[Br:1][CH:20]1[NH:21][CH2:22][CH2:23][N:18]([C:15]2[CH:14]=[CH:13][C:12]([Cl:11])=[CH:17][CH:16]=2)[CH2:19]1.[CH3:2][C:3]([CH3:8])([CH3:7])[CH:4]=[O:5]

Participants

7

Reactant 3

HCID 81531DiisopropylethylamineHCID 2719323-Bromo-2,2-dimethylpropanoic acidHCID 12212341Piperazine, 1-(4-chlorophenyl)-, hydrochloride (1:2)

Product 1

HCID 866357763-Bromo-1-(4-chlorophenyl)piperazine 2,2-dimethylpropan-1-oneYield 29.3%

Reagents, catalysts & solvents 3

HCID 6228DimethylformamideSolventHCID 6344DichloromethaneSolventHCID 24386Thionyl ChlorideSolvent

Conditions

Temperature
0 °C

Procedure

3-Bromo-2,2-dimethylpropionic acid (1.50 g, 8.29 mmol) was dissolved in thionyl chloride (10 mL) and DMF (0.1 mL). The reaction mixture was heated at reflux for 1.5 hours and then concentrated in vacuo, The residue was dissolved in DCM (10 mL) and added to a solution of 4-chlorophenyl piperazine dihydrochloride (2.35 g, 8.70 mmol) and DIPEA (5.05 mL, 29.0 mmol) in DCM (20 mL) at 0° C. The reaction mixture was stirred at 0° C. for 2 hours and then concentrated in vacuo. The residue was dissolved in DCM (100 mL) and washed with 10% citric acid solution (50 mL), sat aq NaHCO3 solution (50 mL), brine (50 mL), dried (MgSO4) and concentrated in vacuo. The resulting residue was purified using normal phase column chromatography (eluting with heptane, followed by a 1:1 mixture of EtOAc:heptane) to give 3-bromo-1-(4-chlorophenyl)piperazine-2,2-dimethyl-propan-1-one (0.87 g, 29.3%) as a yellow solid.

Workup

  1. temperatureThe reaction mixture was heated
  2. temperatureat reflux for 1.5 hours
  3. concentrationconcentrated in vacuo
  4. dissolutionThe residue was dissolved in DCM (10 mL)
  5. concentrationconcentrated in vacuo
  6. dissolutionThe residue was dissolved in DCM (100 mL)
  7. washwashed with 10% citric acid solution (50 mL)
  8. dry with materialdried (MgSO4)
  9. concentrationconcentrated in vacuo
  10. customThe resulting residue was purified
  11. washeluting with heptane
  12. additionfollowed by a 1:1 mixture of EtOAc

Sources & evidence

ORD record
ord-1ddbff1a4f0c4fd78f75d394fac43362
Source dataset
uspto-grants-2012_01
Patent number
US08093248B2

Linked notes

Loading…