반응 #2007

반응 방정식

benzotriazol-1-yloxytris(dimethylamino)phosphonium hexafluorophosphate

D-Homophenylalanine benzyl ester

triethylamine

N-(t-butoxycarbonyl)-α-methylalanine

→

(R)-α-[(2-t-Butoxycarbonylamino-2-methyl-1-oxopropyl)amino]benzenebutanoic acid benzyl ester

용매

methylene chloride

methylene chloride

반응 조건

후처리

1. 1
   workup.STIRRINGThe reaction mixture was stirred at room temperature for 2.5 h
2. 2
   기타then quenched
3. 3
   workup.ADDITIONby adding saturated brine (25 ml)
4. 4
   추출The two phase system was extracted with methylene chloride (3×25 ml)
5. 5
   건조the combined methylene chloride extracts dried over magnesium sulfate powder
6. 6
   여과filtered
7. 7
   기타evaporated on a rotary evaporator under reduced pressure
8. 8
   기타to give a colorless oil that
9. 9
   기타on standing at room temperature
10. 10
    기타chromatographed on silica gel using an eluant
11. 11
    기타The product was isolated
12. 12
    기타after evaporation of the volatiles as a white solid

실험 절차

D-Homophenylalanine benzyl ester (0.87 g; 3.23 mmol), triethylamine (900 ml) and N-(t-butoxycarbonyl)-α-methylalanine (656 mg; 3.23 mmol) were dissolved in dry methylene chloride (6.5 ml) and benzotriazol-1-yloxytris(dimethylamino)phosphonium hexafluorophosphate (BOP-reagent) (1.43 g; 3.23 mmol) was added with stirring in small batches over 10 minutes. The reaction mixture was stirred at room temperature for 2.5 h then quenched by adding saturated brine (25 ml). The two phase system was extracted with methylene chloride (3×25 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 colorless oil that solidified to an off white solid on standing at room temperature. This solid 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 1:3 v/v. The product was isolated after evaporation of the volatiles as a white solid. The yield of the desired product was 1.30 g (88.5%). FAB-MS: -calculated for C26H34N2O5 454.2; found 455.5 (M+1).

출처