Diisopropylethylamine → 1-Tert-butoxycarbonyl-3-benzhydrylpiperazine

HRID 1006318Notes

Reaction equation

HRID 1006318 reaction equation
[C:1](=[O:12])([O:7][C:8]([CH3:11])([CH3:10])[CH3:9])OC(C)(C)C.Cl.Cl.[CH:15]([CH:28]1[CH2:33][NH:32][CH2:31][CH2:30][NH:29]1)([C:22]1[CH:27]=[CH:26][CH:25]=[CH:24][CH:23]=1)[C:16]1[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=1.C(N(CC)C(C)C)(C)C>CN(C)C=O>[C:8]([O:7][C:1]([N:32]1[CH2:31][CH2:30][NH:29][CH:28]([CH:15]([C:16]2[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=2)[C:22]2[CH:27]=[CH:26][CH:25]=[CH:24][CH:23]=2)[CH2:33]1)=[O:12])([CH3:9])([CH3:10])[CH3:11]

Participants

5

Reactant 3

HCID 81531DiisopropylethylamineHCID 10219638Carbonic acid, bis(1,1-dimethylethyl) esterHCID 226747432-Benzhydrylpiperazine dihydrochloride

Product 1

HCID 226748001-Tert-butoxycarbonyl-3-benzhydrylpiperazineYield 70.5%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

Di-tert-butyl carbonate (996 mg) was added to a mixture of 2-benzhydrylpiperazine dihydrochloride (1.65 g) and N,N-diisopropylethylamine (3.5 ml) in N,N-dimethylformamide (17 ml) under ice-cooling. After being stirred at same temperature for 2 hours, the mixture was poured into ice-water and extracted with ethyl acetate. The extract was washed with brine, dried over sodium sulfate and evaporated under reduced pressure to give a crude oil. The oil was purified by column chromatography on silica gel using a mixed solvent of dichloromethane and methanol (50:1) to give 1-tert-butoxycarbonyl-3-benzhydrylpiperazine (1.26 g) as a colorless powder.

Workup

  1. temperaturecooling
  2. extractionextracted with ethyl acetate
  3. washThe extract was washed with brine
  4. dry with materialdried over sodium sulfate
  5. customevaporated under reduced pressure
  6. customto give a crude oil
  7. customThe oil was purified by column chromatography on silica gel using a mixed solvent of dichloromethane and methanol (50:1)

Sources & evidence

ORD record
ord-a028d704e8994664bedbc37322bf8650
Source dataset
uspto-grants-2004_09
Patent number
US06787543B2

Reaction notes

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