Potassium Iodide → 4-Benzhydrylpiperazin-2-one

HRID 1667135Notes

Reaction equation

HRID 1667135 reaction equation
O=C1NCCN(C(OC(C)(C)C)=O)C1.FC(F)(F)C(O)=O.FC(F)(F)C(O)=O.[NH:29]1[CH2:34][CH2:33][NH:32][CH2:31][C:30]1=[O:35].Br[CH:37]([C:44]1[CH:49]=[CH:48][CH:47]=[CH:46][CH:45]=1)[C:38]1[CH:43]=[CH:42][CH:41]=[CH:40][CH:39]=1.C(=O)([O-])[O-].[K+].[K+].[I-].[K+]>C(Cl)Cl.CN(C)C=O>[CH:37]([N:32]1[CH2:33][CH2:34][NH:29][C:30](=[O:35])[CH2:31]1)([C:38]1[CH:43]=[CH:42][CH:41]=[CH:40][CH:39]=1)[C:44]1[CH:49]=[CH:48][CH:47]=[CH:46][CH:45]=1

Participants

9

Reactant 6

HCID 4875Potassium IodideHCID 6422Trifluoroacetic acidHCID 11430Potassium CarbonateHCID 236603BromodiphenylmethaneHCID 3157178Tert-butyl 3-oxopiperazine-1-carboxylateHCID 67358098Piperazin-2-one 2,2,2-trifluoroacetate

Product 1

HCID 119759334-Benzhydrylpiperazin-2-one

Reagents, catalysts & solvents 2

HCID 6228DimethylformamideSolventHCID 6344DichloromethaneSolvent

Procedure

tert-Butyl 3-oxopiperazine-1-carboxylate (0.6 g, 3 mmol) in methylene chloride (10 mL) was treated with trifluoroacetic acid (3 mL) at room temperature for 1 hour. The reaction mixture was concentrated and the obtained trifluoroacetic salt of 2-piperazinone was used without purification. To a piperazin-2-one 2,2,2-trifluoroacetate (0.4 g, 1.87 mmol) solution in N,N-dimethylformamide (3 mL) was added bromodiphenylmethane (0.45 g, 1.87 mmol), potassium carbonate (0.78 g, 5.7 mmol) and catalytic amount of potassium iodide and the reaction mixture was stirred at ambient temperature overnight. Then it was evaporated, partitioned in H2O/methylene chloride. The organic layer was dried over MgSO4, evaporated in vacuo and chromatographed on silica gel eluting with 30% ethyl acetate/hexane and then with 10% methanol/dichloromethane/1% ammonium hydroxide to yield the title compound. 1H NMR (300 MHz, DMSO-d6) δ ppm 7.80 (s, 1H), 7.46 (m, 4H), 7.31 (m, 4H), 7.21 (m, 2H), 4.37 (s, 1H), 3.17 (m, 2H), 2.79 (s, 2H); MS/DCI 267 (M+H)+.

Workup

  1. concentrationThe reaction mixture was concentrated
  2. customthe obtained trifluoroacetic salt of 2-piperazinone was used without purification
  3. customThen it was evaporated
  4. custompartitioned in H2O/methylene chloride
  5. dry with materialThe organic layer was dried over MgSO4
  6. customevaporated in vacuo
  7. customchromatographed on silica gel eluting with 30% ethyl acetate/hexane

Sources & evidence

ORD record
ord-8632b8e426a14ce9b020a2f5356a6ceb
Source dataset
uspto-grants-2011_10
Patent number
US08044069B2

Reaction notes

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