Pyridine → N-(5-bromo-pyridin-2-yl)-2(R)-(3-chloro-4-methanesulfonyl-phenyl)-3-cyclopentyl-propionamide

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A solution of triphenylphosphine (238 mg, 0.91 mmol) in methylene chloride (10 mL) was cooled to 0° C. and then treated with N-bromosuccinimide (183 mg, 1.03 mmol). The reaction mixture was stirred at 0° C. until it was completely dissolved and became light purple in color. The reaction mixture was then treated with 2(R)-(3-chloro-4-methanesulfonyl-phenyl)-3-cyclopentyl-propionic acid (prepared in Example 97, 200 mg, 0.61 mmol). The reaction mixture was stirred at 0° C. for 20 min and then warmed to 25° C. where it was stirred for 30 min. After such time, the reaction mixture was treated with 2-aminopyridine (85 mg, 0.91 mmol) and pyridine (0.088 mL, 1.09 mmol), and the reaction mixture was stirred at 25° C. for 16 h. The reaction was then diluted with water (10 mL) and then extracted with methylene chloride (3×15 mL). The combined organic layers were dried over sodium sulfate, filtered, and concentrated in vacuo. Biotage chromatography (FLASH 40S, Silica, 60/40 hexanes/ethyl acetate) afforded N-(5-bromo-pyridin-2-yl)-2(R)-(3 -chloro-4-methanesulfonyl-phenyl)-3 -cyclopentyl-propionamide (222 mg, 76%) as an off-white foam: [α]23589 =−48.6°(c=0.105, chloroform); EI-HRMS m/e calcd for C20H22BrCIN2O3S (M+) 484.0223, found 484.0223.

Herkunft & Nachweise