Benzyl chloroformate → Benzyl 3-pyrroline-1-carboxylate

HRID 1666687Notes

Reaction equation

HRID 1666687 reaction equation
[NH:1]1[CH2:5][CH:4]=[CH:3][CH2:2]1.C(N(CC)C(C)C)(C)C.Cl[C:16]([O:18][CH2:19][C:20]1[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=1)=[O:17]>C(Cl)(Cl)Cl>[N:1]1([C:16]([O:18][CH2:19][C:20]2[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=2)=[O:17])[CH2:5][CH:4]=[CH:3][CH2:2]1

Participants

5

Reactant 3

HCID 10387Benzyl chloroformateHCID 660593-PyrrolineHCID 81531Diisopropylethylamine

Product 1

HCID 643471Benzyl 3-pyrroline-1-carboxylateYield 97.1%

Reagents, catalysts & solvents 1

HCID 6212ChloroformSolvent2×

Procedure

A mixture of 3-pyrroline (9.1 g), N,N-diisopropylethylamine (28 mL), and chloroform (46 mL) was ice-cooled, benzyl chloroformate (26 g) was added dropwise, and then the mixture was stirred at room temperature for 15 h. The reaction solution was diluted with chloroform, washed with saturated aqueous sodium hydrogencarbonate, saturated aqueous ammonium chloride, and saturated brine, and then dried with anhydrous sodium sulfate. The desiccant was removed by filtration, then the filtrate was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography (hexane/ethyl acetate=7:3) to obtain benzyl 2,5-dihydropyrrole-1-carboxylate (26 g).

Workup

  1. temperaturecooled
  2. washwashed with saturated aqueous sodium hydrogencarbonate, saturated aqueous ammonium chloride, and saturated brine
  3. dry with materialdried with anhydrous sodium sulfate
  4. customThe desiccant was removed by filtration
  5. concentrationthe filtrate was concentrated under reduced pressure
  6. customthe residue was purified by silica gel column chromatography (hexane/ethyl acetate=7:3)

Sources & evidence

ORD record
ord-1262e48804634f42afaf3d5966ed3611
Source dataset
uspto-grants-2011_10
Patent number
US08044068B2

Reaction notes

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