Water → 4-[2,2-Bis-(4-chloro-phenyl)-ethyl]-piperazine-1-carboxylic acid tert-butyl ester

HRID 1798354Notes

Reaction equation

HRID 1798354 reaction equation
[Cl:1][C:2]1[CH:7]=[CH:6][C:5]([CH:8]([C:11]2[CH:16]=[CH:15][C:14]([Cl:17])=[CH:13][CH:12]=2)[CH:9]=O)=[CH:4][CH:3]=1.[C:18]([N:25]1[CH2:30][CH2:29][NH:28][CH2:27][CH2:26]1)([O:20][C:21]([CH3:24])([CH3:23])[CH3:22])=[O:19].C([BH3-])#N.[Na+].O>CO>[C:21]([O:20][C:18]([N:25]1[CH2:30][CH2:29][N:28]([CH2:9][CH:8]([C:11]2[CH:16]=[CH:15][C:14]([Cl:17])=[CH:13][CH:12]=2)[C:5]2[CH:6]=[CH:7][C:2]([Cl:1])=[CH:3][CH:4]=2)[CH2:27][CH2:26]1)=[O:19])([CH3:24])([CH3:22])[CH3:23]

Participants

6

Reactant 4

HCID 962WaterHCID 143452tert-Butyl piperazine-1-carboxylateHCID 167694Bis(4-chlorophenyl)acetaldehydeHCID 5003444Sodium cyanoborohydride

Product 1

HCID 593319524-[2,2-Bis-(4-chloro-phenyl)-ethyl]-piperazine-1-carboxylic acid tert-butyl esterYield 11.1%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

To a solution of bis-(4-chloro-phenyl)-acetaldehyde (3.74 mmol) in methanol under a nitrogen atmosphere, N-BOC-piperazine (1.05 g, 5.61 mmol) was added, the reaction mixture was stirred for 1 hour before addition of sodium cyanoborohydride (0.28 g, 4.49 mmol). The reaction mixture was stirred for 18 hours, water added (3 ml) and the solvent removed under reduced pressure. The residue was partitioned between dichloromethane and water, the organic layer was separated, dried (MgSO4), filtered and concentrated. Purified over flash silica chromatography eluting with ethyl acetate/petroleum ether (3:7) to yield the title compound (0.18 g, 11% yield for steps 30A and 30B combined). LC/MS: (PS-A2) Rt 2.66 [M-BOC+H]+335.02.

Workup

  1. customthe solvent removed under reduced pressure
  2. customThe residue was partitioned between dichloromethane and water
  3. customthe organic layer was separated
  4. dry with materialdried (MgSO4)
  5. filtrationfiltered
  6. concentrationconcentrated
  7. customPurified over flash silica chromatography
  8. washeluting with ethyl acetate/petroleum ether (3:7)

Sources & evidence

ORD record
ord-a6fce814d9af43e7b313a274af2fd718
Source dataset
uspto-grants-2013_01
Patent number
US08343953B2

Reaction notes

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