반응 #1702034

반응 방정식

HCl

diisopropylethylamine

acetyl bromide

5

3-Methoxydodecanal

AlMe3

→

6

수율 77.3%

(4R)-4-((2RS)-2-Methoxyundecyl)oxetan-2-one

수율 77.3%

용매

CH2Cl2

CH2Cl2

반응 조건

후처리

1. 1
   온도cooled to −45° C.
2. 2
   workup.STIRRINGThe resulting pale yellow solution was stirred for 14 h at −45° C.
3. 3
   온도warmed to rt
4. 4
   workup.ADDITIONpoured into a separatory funnel
5. 5
   세척The organic layer was washed with saturated NaHCO3, brine
6. 6
   건조dried (Na2SO4)
7. 7
   기타The solvent was removed in vacuo
8. 8
   기타the yellow oily product was purified by chromatography on SiO2 (4% EtOAc/hexanes to 6% EtOAc/hexanes)

실험 절차

A solution of N,N′-(1R,1′R)-1,1′-(benzylazanediyl)bis(2-methylpropane-1,1-diyl)bis(1,1,1-trifluoromethanesulfonamide) (81.2 mg, 0.15 mmol, 30 mol %) in CH2Cl2 (1 mL) was treated at rt under N2 slowly with a solution of AlMe3 (10.8 mg, 0.15 mmol) in CH2Cl2 (0.5 mL). The mixture was stirred at room temperature (rt) for 2 h, cooled to −45° C. and treated sequentially with diisopropylethylamine (11 mg, 1.7 equiv), acetyl bromide (117 mg, 1.9 equiv) and 5 (107 mg, 0.500 mmol, 1.0 equiv). The resulting pale yellow solution was stirred for 14 h at −45° C., warmed to rt, and poured into a separatory funnel containing 0.1 N HCl (10) mL). The organic layer was washed with saturated NaHCO3, brine, and dried (Na2SO4). The solvent was removed in vacuo and the yellow oily product was purified by chromatography on SiO2 (4% EtOAc/hexanes to 6% EtOAc/hexanes) to give 6 (99.1 mg, 77%) as a colorless oil: 1H NMR (CDCl3) 4.8-4.65 (m, 1H), 3.60-3.50 (m, 1H), 3.3-3.2 (m, 1H), 3.35, 3.32 (2s, 3H), 3.22-3.08 (m, 1H), 2.18-1.82 (m, 2H) 1.65-1.35 (m, 2H), 1.35-1.20 (m, 14H), 0.90-0.80 (m, 3H).

출처