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

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A solution of triphenylphosphine (238 mg, 0.91 mmol) in methylene chloride (6 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 became homogeneous. The resulting light purple reaction mixture was then treated with 2(R)-(3-chloro-4-methanesulfonyl-phenyl)-3-cyclopentyl-propionic acid (prepared as in Example 137, 200 mg, 0.61 mmol). The reaction mixture was stirred at 0° C. for 20 min and then allowed to warm to 25° C. where it was stirred for 30 min. The reaction mixture was then treated with 2-amino-5-methylthiazole (104 mg, 0.91 mmol) and pyridine (0.15 mL, 1.82 mmol), and the resulting reaction mixture was stirred at 25° C. for 16 h. The reaction was then diluted with water (15 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, 55/45 hexanes/ethyl acetate) afforded 2(R)-(3-chloro-4-methanesulfonyl-phenyl)-3-cyclopentyl-N-(5-methyl-thiazol-2-yl)-propionamide (201 mg, 78%) as a orange foam: [α]23589=−72.7° (c=0.055, chloroform); EI-HRMS m/e calcd for C19H23ClN2O3S2 (M+) 426.0838, found 426.0837.

Herkunft & Nachweise