반응 #798127

ord-48d3074824cb48a3a3dba3b1c530618b

반응 조건

상세 조건
See reaction.notes.procedure_details.

후처리

  1. 1
    기타does not exceed 0° C
  2. 2
    기타does not exceed 0° C.
  3. 3
    workup.ADDITIONafter the addition
  4. 4
    workup.STIRRINGstirring for 1 hour
  5. 5
    세척This reaction mixture was washed with 0.5M hydrochloric acid and saturated brine
  6. 6
    건조the organic layer was dried over magnesium sulfate
  7. 7
    workup.DISTILLATIONdistilled off under reduced pressure

실험 절차

A solution of (R)-1-(tert-butoxycarbonyl)-5-oxopyrrolidine-2-carboxylic acid (1.146 g, 5.00 mmol) in dehydrated methylene chloride (25 mL) was cooled to 0° C. under an argon atmosphere and gradually added dropwise isobutyl chloroformate (0.682 g) so that the temperature does not exceed 0° C. Then, triethylamine (0.505 g) was gradually added so that the temperature does not exceed 0° C., followed by stirring 30 minutes, thereby a mixed acid anhydride was prepared in the reaction system. To this reaction mixture was gradually added benzyl hydrazinecarboxylate (0.830 g), after the addition, followed by raising the temperature to room temperature and stirring for 1 hour. This reaction mixture was washed with 0.5M hydrochloric acid and saturated brine, the organic layer was dried over magnesium sulfate and then distilled off under reduced pressure. The resulting residue was subjected to silica gel column chromatography (hexane/ethyl acetate=4/1→0/1→ethyl acetate/methanol=30/1) to afford 1.53 g of the title compound (yield 80.1%).

출처

DOI: 10.6084/m9.figshare.5104873.v1특허: US09181250B2uspto-grants-2015_11