Hydrochloric Acid → 1,4-Bis(benzyloxycarbonyl)piperazine-2-carboxylic acid

HRID 730889Notes

Reaction equation

HRID 730889 reaction equation
Cl[C:2]([O:4][CH2:5][C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][CH:7]=1)=[O:3].Cl.Cl.[NH:14]1[CH2:19][CH2:18][NH:17][CH2:16][CH:15]1[C:20]([OH:22])=[O:21].[C:23]([O-:26])([O-])=[O:24].[Na+].[Na+].Cl>O>[CH2:5]([O:4][C:2]([N:14]1[CH2:19][CH2:18][N:17]([C:23]([O:26][CH2:5][C:6]2[CH:11]=[CH:10][CH:9]=[CH:8][CH:7]=2)=[O:24])[CH2:16][CH:15]1[C:20]([OH:22])=[O:21])=[O:3])[C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][CH:7]=1

Participants

6

Reactant 4

HCID 313Hydrochloric AcidHCID 10340Sodium CarbonateHCID 10387Benzyl chloroformateHCID 2723757Piperazine-2-carboxylic acid dihydrochloride

Product 1

HCID 226328591,4-Bis(benzyloxycarbonyl)piperazine-2-carboxylic acid

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Conditions

Temperature
0 °C

Procedure

Benzyl chloroformate (3.1 mL, 22 mmol, Aldrich) was added dropwise over a period of 5 min to a mixture of piperazine-2-carboxylic acid dihydrochloride (2.03 g, 10 mmol, Aldrich) and Na2CO3 (4.24 g, 40 mmol) in water (10 mL) with stirring at 0° C. The mixture was stirred at 0° C. for 1 h, 2N HCl (10 mL) was added and the mixture was extracted with EtOAc (3×40 mL). The combined organic extracts were washed with water (10 mL) and brine (20 mL), dried over Na2SO4, and filtered. The filtrate was evaporated in vacuo to give the title compound as a gum, which was used for the next step without additional purification. MS (ESI, pos. ion) m/e: 399 (M+l).

Workup

  1. stirringThe mixture was stirred at 0° C. for 1 h
  2. extractionthe mixture was extracted with EtOAc (3×40 mL)
  3. washThe combined organic extracts were washed with water (10 mL) and brine (20 mL)
  4. dry with materialdried over Na2SO4
  5. filtrationfiltered
  6. customThe filtrate was evaporated in vacuo

Sources & evidence

ORD record
ord-78e8f22010eb4b8d8eccef16872338fe
Source dataset
uspto-grants-2009_09
Patent number
US07582761B2

Reaction notes

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