tert-Butanol → (S)-1-Boc-3-isopropylpiperazine

HRID 25851Notes

Reaction equation

HRID 25851 reaction equation
[OH-:1].[Na+].C(O[C:11]([NH:13][C@H:14]([C:18](O)=O)[CH:15]([CH3:17])[CH3:16])=O)C1C=CC=CC=1.COC(=O)[CH2:24][NH2:25].C(Cl)Cl.[CH3:30][OH:31].[C:32](O)([CH3:35])([CH3:34])[CH3:33]>O>[C:32]([O:1][C:30]([N:25]1[CH2:24][CH2:11][NH:13][C@@H:14]([CH:15]([CH3:16])[CH3:17])[CH2:18]1)=[O:31])([CH3:35])([CH3:34])[CH3:33]

Participants

6

Reactant 4

HCID 6386tert-ButanolHCID 14798Sodium HydroxideHCID 21226129Dichloromethane methanolHCID 69129945N-Benzyloxycarbonyl-valine glycine-methylester

Product 1

HCID 24820348(S)-1-Boc-3-isopropylpiperazineYield 98.37%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Conditions

Temperature
0 °C

Procedure

5.68 ml (14.20 mmol, 1.00 eq.) of a 2.5 N aq. NaOH-solution were added to a solution of 1.82 g (14.19 mmol) 2-(S)-Isopropyl-piperazine (82) in 70 ml tert-Butanol and 70 ml H2O. After cooling to 0° C. 3.10 g (14.20 mmol, 1.00 eq.) Boc-anhydride was added and the mixture was stirred at 0° C. for 1 h. Then the solution was warmed to r.t. and stirred overnight. After evaporating the tert-Butanol the mixture was extracted with CH2Cl2. The comb. org. fractions were dried over Na2SO4 and evaporated. Column chromatography (CH2Cl2/MeOH (10+1)) yielded 3.19 g (13.96 mmol, 98.37%) 3-(S)-Isopropyl-piperazine-1-carboxylic acid tert-butyl ester (85) as a clear oil.

Workup

  1. temperatureThen the solution was warmed to r.t.
  2. stirringstirred overnight
  3. customAfter evaporating the tert-Butanol the mixture
  4. extractionwas extracted with CH2Cl2
  5. dry with materialfractions were dried over Na2SO4
  6. customevaporated

Sources & evidence

ORD record
ord-0d0f7fe44df34cb9916b0ca8ec7f9729
Source dataset
uspto-grants-2005_02
Patent number
US06858600B2

Reaction notes

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