反应 #2008

ord-a50f7cac2645481a8747ad859fb15edc

反应条件

详细条件
See reaction.notes.procedure_details.

后处理

  1. 1
    其他to give a slightly cloudy solution
  2. 2
    workup.STIRRINGThe reaction mixture was stirred at room temperature for 24 h
  3. 3
    其他then quenched
  4. 4
    workup.ADDITIONby adding saturated brine (10 ml)
  5. 5
    萃取The two phase system was extracted with methylene chloride (2×25 ml)
  6. 6
    干燥the combined methylene chloride extracts dried over magnesium sulfate powder
  7. 7
    过滤filtered
  8. 8
    其他evaporated on a rotary evaporator under reduced pressure
  9. 9
    其他to give a cloudy, colorless oil
  10. 10
    其他chromatographed on silica gel using an eluant
  11. 11
    其他The product was isolated
  12. 12
    其他after evaporation of the volatiles as a clear oil

实验过程

D-Homophenylalanine benzyl ester (725 mg; 3.23 mmol) whose preparation was described in Example 7 Step B, triethylamine (750 ml; 5,38 mmol) and 3-t-butoxycarbonylamino-3-methylbutanoic acid (585 mg; 2.69 mmol) were dissolved in dry methylene chloride (10 ml) and BOP (1.19 g, 2.69 mmol) was added with stirring in small batches to give a slightly cloudy solution. The reaction mixture was stirred at room temperature for 24 h then quenched by adding saturated brine (10 ml). The two phase system was extracted with methylene chloride (2×25 ml) and the combined methylene chloride extracts dried over magnesium sulfate powder, filtered and evaporated on a rotary evaporator under reduced pressure to give a cloudy, colorless oil. This material was taken up in the minimum volume of methylene chloride and chromatographed on silica gel using an eluant composed of ethyl acetate and hexanes in the ratio 1:1 v/v. The product was isolated after evaporation of the volatiles as a clear oil. The yield was 710 mg (88.5%). FAB-MS: -calculated for C27H36N2 O5 468.3; found 469.6 (M+1).

来源

DOI: 10.6084/m9.figshare.5104873.v1专利: US05726319uspto-grants-1998_03