Реакция #502121

Уравнение реакции

(2S)-2-(6-methoxy(2-naphthyl))propanoic acid

((4S)-2,2,4-trimethyl-1,3-dioxolan-4-yl)methan-l-ol

→

title compound

Выход 96.5%

((4R)-2,2,4-Trimethyl-1,3-dioxolan-4-yl)methyl(2S)-2-(6-methoxy(2-naphthyl))propanoate

Выход 96.5%

Растворители

dichloromethane

Условия реакции

Обработка

1. 1
   Другоеquenched with water
2. 2
   ПромывкаThe organic layer was washed with brine
3. 3
   Сушкаdried over sodium sulfate
4. 4
   Фильтрацияfiltered
5. 5
   Другоеsolvent was evaporated under reduced pressure
6. 6
   ДругоеThe product was purified by column chromatography over silica gel eluting with 20% ethyl acetate in hexane

Методика

To a solution of (2S)-2-(6-methoxy(2-naphthyl))propanoic acid (naproxen, 32.2 g, 0.14 mol) and ((4S)-2,2,4-trimethyl-1,3-dioxolan-4-yl)methan-l-ol (15 g, 0.113 mol) in anhydrous dichloromethane (750 mL) were added 1-ethyl-3-(3-dimethylaminopropyl)carbamide hydrochloride (EDAC) (23 g, 0.12 mol) and N,N-dimethylaminopyridine (DMAP, 7.5 g, 61 mmol) at room temperature under nitrogen atmosphere. The reaction mixture was stirred at room temperature overnight, then quenched with water. The organic layer was washed with brine, dried over sodium sulfate, filtered, and solvent was evaporated under reduced pressure. The product was purified by column chromatography over silica gel eluting with 20% ethyl acetate in hexane to give the title compound (37.5 g, 96.5% yield) as a white solid, mp 65-66° C. 1H NMR (CDCl3) δ7.75 (d, J=8.7 Hz, 1H), 7.73 (d, J=1.2 Hz, 1H), 7.46 (dd, J=8.4 and 1.7 Hz, 1H), 7.15 (m, 2H), 4.27 (m, 1H), 4.19 (m, 2H), 4.03-3.92 (m, 2H), 3.96 (s, H), 3.69 (dd, J=8.4 and 6.0 Hz, 1H), 1.64 (d, J=7.1 Hz, 3H), 1.40 (s, 3H), 1.37 (s, 3H); 13C NMR (75 MHz, CDCl3) δ 174.4, 157.6, 135.3, 133.7, 129.2, 128.8, 127.1, 126.1, 125.9, 119.0, 109.7, 105.5, 73.4, 66.2, 64.8, 55.2, 45.2, 26.5, 25.3, 18.4; LRMS (APIMS) m/z 362 (M+NH4)+.

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