Hydroxyamine hydrochloride → N-(5-bromo-pyrazin-2-yl)-2-(3-chloro-4-methanesulfonyl-phenyl)-3-(3-hydroxyimino-cyclopentyl)-propionamide

Participants

Reaction Conditions

Reaction Steps

A solution of N-(5-bromo-pyrazin-2-yl)-2-(3-chloro-4-methanesulfonyl-phenyl)-3-(3-oxo-cyclopentyl)-propionamide (prepared as in Example 49, 190 mg, 0.38 mmol) and hydroxylamine hydrochloride (40 mg, 0.57 mmol) in methanol (0.90 mL) and pyridine (0.90 mL) was heated under reflux for 3 h. The reaction mixture was allowed to cool to 25° C. and was then concentrated in vacuo. The resulting residue was diluted with water (50 mL) and extracted with ethyl acetate (50 mL). The organic layers were washed with a 1N aqueous hydrochloric acid solution (50 mL) and a saturated aqueous sodium chloride solution, dried over magnesium sulfate, filtered, and concentrated in vacuo. Biotage chromatography (FLASH 40S, Silica, 75% ethyl acetate/hexanes) afforded the N-(5-bromo-pyrazin-2-yl)-2-(3-chloro-4-methanesulfonyl-phenyl)-3-(3-hydroxyimino-cyclopentyl)-propionamide 77%) as a yellow foam: mp 100–106° C.; (ES)+-HRMS m/e calcd for C19H20BrClN4O4S (M+H)+ 515.0150 found 515.0154.

Provenance & Evidence