反应详情

温度

0 °C

A solution of triphenylphosphine (344 mg, 1.31 mmol) in methylene chloride (10 mL) cooled to 0° C. was treated with N-bromosuccinimide (263 mg, 1.48 mmol). The reaction solution was stirred at 0° C. for 5 min. At this time, 3-cyclopentyl-2(R)-(3,4-dichloro-phenyl)propionic acid (250 mg, 0.87 mmol) was added. The reaction was allowed to slowly warm to 25° C. over 45 min. At this time, 5-chloro-2-aminopyridine (145 mg, 1.13 mmol) and pyridine (0.11 mL, 1.31 mmol) were added to the reaction mixture. The reaction was stirred at 25° C. for 20 h. At this time, the reaction was diluted with water (10 mL) and extracted with methylene chloride (3×10 mL). The combined organic layers were dried over sodium sulfate, filtered, and concentrated in vacuo. Flash chromatography (Merck Silica gel 60, 230-400 mesh, 90/10 hexanes/ethyl acetate) afforded N-(5-chloro-pyridin-2-yl)3-cyclopentyl-2-(R)-(3,4-dichloro-phenyl)-propionamide (289 mg, 84%) as a white solid: mp 125-128° C.; [α]23589=−65.6° (c=0.16, chloroform); EI-HRMS m/e calcd for C19H19Cl3N2O (M+) 396.0563, found 396.0565.

1. temperatureto slowly warm to 25° C. over 45 min
2. stirringThe reaction was stirred at 25° C. for 20 h
3. extractionextracted with methylene chloride (3×10 mL)
4. dry with materialThe combined organic layers were dried over sodium sulfate
5. filtrationfiltered
6. concentrationconcentrated in vacuo