Реакция #1947300

Уравнение реакции

(4-chloro-phenyl)-acetic acid ethyl ester

lithium diisopropylamide

iodomethylcyclopentane

→

2-(4-chloro-phenyl)-3-cyclopentyl-propionic acid ethyl ester

Выход 90.9%

Растворители

tetrahydrofuran hexamethylphosphoramide

hexamethylphosphoramide

Условия реакции

Обработка

1. 1
   workup.STIRRINGThe reaction mixture was stirred at −78° C. for 4 h
2. 2
   ТемператураThe reaction was warmed to 25° C.
3. 3
   workup.STIRRINGstirred at 25° C. for 16 h
4. 4
   ДругоеThe reaction mixture was then quenched by the dropwise addition of a saturated aqueous ammonium chloride solution (20 mL)
5. 5
   workup.ADDITIONThis mixture was poured into water (100 mL)
6. 6
   Экстракцияextracted with ethyl acetate (3×50 mL)
7. 7
   СушкаThe organics were dried over sodium sulfate
8. 8
   Фильтрацияfiltered
9. 9
   Концентрированиеconcentrated in vacuo

Методика

A solution of freshly prepared lithium diisopropylamide (23.0 mL of 0.31M stock solution, 7.13 mmol) cooled to −78° C. was treated with (4-chloro-phenyl)-acetic acid ethyl ester (1.28 g, 6.48 mmol) in tetrahydrofuran/hexamethylphosphoramide (16.1 mL, 3:1). The resulting solution was stirred at −78° C. for 45 min. At this time, the reaction was treated with a solution of iodomethylcyclopentane (1.50 mg, 7.13 mmol) in hexamethylphosphoramide (1 mL). The reaction mixture was stirred at −78° C. for 4 h. The reaction was warmed to 25° C. and stirred at 25° C. for 16 h. The reaction mixture was then quenched by the dropwise addition of a saturated aqueous ammonium chloride solution (20 mL). This mixture was poured into water (100 mL) and extracted with ethyl acetate (3×50 mL). The organics were dried over sodium sulfate, filtered, and concentrated in vacuo. Flash chromatography (Merck Silica gel 60, 230-400 mesh, 75/25 hexanes/ethyl acetate) afforded 2-(4-chloro-phenyl)-3-cyclopentyl-propionic acid ethyl ester (1.65 g, 90.9%) as a yellow oil: EI-HRMS m/e calcd for C16H21Cl2O2 (M+) 280.1230, found 280.1227.

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