Sodium hydride → Tert-butyl 4-(2-{[tert-butyl(dimethyl)silyl]oxy}ethyl)-3-oxopiperazine-1-carboxylate

HRID 2105882Notes

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][CH2:19][O:20][Si:21]([C:24]([CH3:27])([CH3:26])[CH3:25])([CH3:23])[CH3:22]>CN(C)C=O>[C:3]([O:7][C:8]([N:10]1[CH2:15][CH2:14][N:13]([CH2:18][CH2:19][O:20][Si:21]([C:24]([CH3:27])([CH3:26])[CH3:25])([CH3:23])[CH3:22])[C:12](=[O:16])[CH2:11]1)=[O:9])([CH3:6])([CH3:4])[CH3:5]

Participants

Conditions

Temperature: 0 °C

Procedure

Sodium hydride (0.35 g, 8.6 mmol, 60% in mineral oil) was added to a solution of 4-tert-butyloxycarbonyl-piperazin-2-one (0.86 g, 4.3 mmol) in dimethylformamide (20.0 mL) at 0° C. The reaction was stirred at 0° C. for 0.5 h. To this mixture was added 2-bromoethoxy-tert-butyldimethylsilane (2.3 mL, 10.8 mmol) and the reaction was stirred for 2 h at room temperature. The reaction mixture was quenched with a dilute aqueous solution of sodium bicarbonate and extracted with methylene chloride. The organic extracts were washed with brine and dried over anhydrous sodium sulfate. Purification of the crude residue by flash column chromatography (silica gel, eluting with 20% ethyl acetate in hexanes) gave 4-tert-butyloxycarbonyl-1-[2-(tert-butyldimethylsilyloxy)ethyl]-piperazin-2-one (1.17 g, 76%).

Workup

stirringthe reaction was stirred for 2 h at room temperature
customThe reaction mixture was quenched with a dilute aqueous solution of sodium bicarbonate
extractionextracted with methylene chloride
washThe organic extracts were washed with brine
dry with materialdried over anhydrous sodium sulfate
customPurification of the crude residue
washby flash column chromatography (silica gel, eluting with 20% ethyl acetate in hexanes)

Sources & evidence

ORD record: ord-a09c86b8619a4693b223ead4edce6b44
Source dataset: uspto-grants-2009_08
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US07579368B2

Reaction notes

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