Benzyl chloroformate → N-4-Boc-N-1-Cbz-2-piperazine carboxylic acid

HRID 1757754Notes

Reaction equation

[C:1]([O:5][C:6]([N:8]1[CH2:13][CH2:12][NH:11][CH:10]([C:14]([OH:16])=[O:15])[CH2:9]1)=[O:7])([CH3:4])([CH3:3])[CH3:2].Cl[C:18]([O:20][CH2:21][C:22]1[CH:27]=[CH:26][CH:25]=[CH:24][CH:23]=1)=[O:19]>[OH-].[Na+]>[CH2:21]([O:20][C:18]([N:11]1[CH2:12][CH2:13][N:8]([C:6]([O:5][C:1]([CH3:4])([CH3:2])[CH3:3])=[O:7])[CH2:9][CH:10]1[C:14]([OH:16])=[O:15])=[O:19])[C:22]1[CH:27]=[CH:26][CH:25]=[CH:24][CH:23]=1

Participants

Conditions

Temperature: 0 °C

Procedure

0.1 g of 4-(tert.butoxycarbonyl)-piperazine-2-carboxylic acid was dissolved in 10 ml of 1N sodium hydroxide solution, cooled to 0° C.and treated with 0.2 g of benzyl chloroformate. The mixture was allowed to warm to room temperature and was then stirred overnight. The mixture was extracted with diethyl ether. The aqueous phase was then acidified to pH 4with 2M hydrochloric acid and extracted with ethyl acetate to give 0.06 g of 1-(benzyloxycarbonyl)-4-(tert.butoxycarbonyl)-2-piperazinecarboxylic acid as a white solid: MS: m/e 365 [M+H]+.

Workup

temperatureto warm to room temperature
extractionThe mixture was extracted with diethyl ether
extractionextracted with ethyl acetate

Sources & evidence

ORD record: ord-af89c6e5bd2447f2b6d682853b09d993
Source dataset: uspto-grants-1995_08
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US05446161

Reaction notes

Loading…