Реакция #8852

Уравнение реакции

ammonium chloride

propionaldehyde

tert-butyl 4-acetyl-4-methoxypiperidine-1-carboxylate

tert-Butyl 4-acetyl-4-methoxypiperidine-1-carboxylate

lithium diisopropylamine

→

title compound

Выход 55.9%

tert-Butyl 4-(3-hydroxy-1-oxopent-1-yl)-4-methoxypiperidine-1-carboxylate

Выход 55.9%

Растворители

tetrahydrofuran

Условия реакции

Обработка

1. 1
   Экстракцияextracted three times with diethyl ether
2. 2
   Промывкаwashed with saturated sodium chloride solution
3. 3
   Сушкаdried over sodium sulfite
4. 4
   Фильтрацияfiltered
5. 5
   Концентрированиеconcentrated
6. 6
   ДругоеThe residue was purified by flash chromatography
7. 7
   Промывкаeluting with 40% ethyl acetate/hexanes

Методика

To a solution of tert-butyl 4-acetyl-4-methoxypiperidine-1-carboxylate (0.589 g, 2.29 mmol) from Step A in tetrahydrofuran (20 mL) at −78° C. was added lithium diisopropylamine (0.650 mL, 0.974 mmol) followed by propionaldehyde (0.266 g, 0.330 mL, 4.58 mmol). After 5 min, the reaction mixture was poured into saturated ammonium chloride, and extracted three times with diethyl ether. The organic layers were combined, washed with saturated sodium chloride solution, dried over sodium sulfite, filtered, and concentrated. The residue was purified by flash chromatography eluting with 40% ethyl acetate/hexanes to afford the title compound (0.404 g). MS/EI (acetonitrile/water): m/z 216.1 (M+1−BOC) retention time=2.69 min.

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