Реакция #1702034

Уравнение реакции

HCl

diisopropylethylamine

acetyl bromide

5

3-Methoxydodecanal

AlMe3

→

6

Выход 77.3%

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

Выход 77.3%

Растворители

CH2Cl2

CH2Cl2

Условия реакции

Обработка

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

Методика

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).

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