반응 #624560

반응 방정식

Boc-tert-leucine

CH2Cl2

benzyl alcohol

EDC

→

(R)-benzyl 2-(tert-butoxycarbonylamino)-3,3-dimethylbutanoate

용매

diethyl ether

반응 조건

후처리

1. 1
   workup.ADDITIONA 2-dram vial containing a small stirbar
2. 2
   세척The mixture was washed with water (2×10 mL), saturated aqueous NaHCO3 (10 mL), and brine (10 mL)
3. 3
   건조The organic layer was dried over Na2SO4
4. 4
   농축concentrated under reduced pressure
5. 5
   기타The residue can be further purified by flash column chromatography on silica gel (7:1 hexanes/Et2O)
6. 6
   기타Both the crude and purified samples
7. 7
   기타=9.08 min
8. 8
   기타tR(minor)=15.80 min.

실험 절차

A 2-dram vial containing a small stirbar was charged with Boc-tert-leucine (10a) (10 mg, 0.04 mmol), CH2Cl2 (1 mL), 4-dimethylaminopyridine (2 mg, 0.02 mmol, 0.5 equiv), benzyl alcohol (20 μL, 0.2 mmol, 5 equiv), and EDC (20 mg, 0.1 mmol, 2.5 equiv). The solution was stirred at room temperature for 3 h, and then diluted with 10 mL of diethyl ether. The mixture was washed with water (2×10 mL), saturated aqueous NaHCO3 (10 mL), and brine (10 mL). The organic layer was dried over Na2SO4 and concentrated under reduced pressure. The residue can be further purified by flash column chromatography on silica gel (7:1 hexanes/Et2O). Both the crude and purified samples were analyzed by chiral HPLC analysis: (AD-H, 1 mL/min, 5% IPA/hexanes, 210 nm): tR(major)=9.08 min, tR(minor)=15.80 min.

출처