Sodium hydride → 4-Cyclopropylmethyl-3-oxopiperazine-1-carboxylic acid tert-butyl ester

HRID 1581638Notes

Reaction equation

HRID 1581638 reaction equation
[H-].[Na+].[C:3]([O:7][C:8]([N:10]1[CH2:15][CH2:14][NH:13][C:12](=[O:16])[CH2:11]1)=[O:9])([CH3:6])([CH3:5])[CH3:4].Br[CH2:18][CH:19]1[CH2:21][CH2:20]1>CN(C)C(=O)C.O>[C:3]([O:7][C:8]([N:10]1[CH2:15][CH2:14][N:13]([CH2:18][CH:19]2[CH2:21][CH2:20]2)[C:12](=[O:16])[CH2:11]1)=[O:9])([CH3:6])([CH3:4])[CH3:5]

Participants

6

Reactant 3

HCID 24758Sodium hydrideHCID 81503BromomethylcyclopropaneHCID 3157178Tert-butyl 3-oxopiperazine-1-carboxylate

Product 1

HCID 670849224-Cyclopropylmethyl-3-oxopiperazine-1-carboxylic acid tert-butyl esterYield 100%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 31374DimethylacetamideSolvent

Procedure

Sodium hydride (60% dispersion in oil) (0.40 g, 10.0 mmol) was added portionwise over 10 min to a solution of 3-oxopiperazine-1-carboxylic acid tert-butyl ester (1.00 g, 5.0 mmol) in N,N-dimethylacetamide (10 ml). The mixture was stirred for 30 min before addition of bromomethylcyclopropane (1.45 ml, 15.0 mmol) and then stirred for a further 18 h. The mixture was diluted with water (100 ml) and extracted with EtOAc (2×100 ml). The combined organic extracts were washed with brine (50 ml), dried over MgSO4 and evaporated to give 4-cyclopropylmethyl-3-oxopiperazine-1-carboxylic acid tert-butyl ester (1.27 g, 100%) as a yellow oil. This oil was dissolved in dichloromethane and hydrogen chloride bubbled through the reaction (2×10 min). The solvent was evaporated to give 1-cyclopropylmethylpiperazin-2-one.HCl (0.95 g, 100%) as a white solid.

Workup

  1. extractionextracted with EtOAc (2×100 ml)
  2. washThe combined organic extracts were washed with brine (50 ml)
  3. dry with materialdried over MgSO4
  4. customevaporated

Sources & evidence

ORD record
ord-34c71b5d338a4d57899b9c485c117888
Source dataset
uspto-grants-2004_05
Patent number
US06730681B2

Reaction notes

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