Sodium Hydroxide → HCID 22315271, compound

Participants

Reaction Conditions

Reaction Steps

A solution of 2-[3-cyclopentyl-2-(3,4-dichlorophenyl)-propionylamino]-thiazole-5-carboxylic acid ethyl ester (prepared as in Example 1(B)(g), 1.0 g, 2.27 mmol) in absolute ethanol (10 mL) was treated with a 1N aqueous sodium hydroxide solution (4.77 mL, 4.77 mmol). The reaction mixture was heated under reflux for 15 h. The reaction mixture was allowed to cool to 25° C. and then concentrated in vacuo to remove absolute ethanol. The resulting yellow residue was acidified to pH=2 with concentrated hydrochloric acid and extracted with ethyl acetate (2×75 mL). The combined organic layers were dried over magnesium sulfate, filtered, and concentrated in vacuo. Recrystallization from ethyl acetate afforded 2-[3-cyclopentyl-2-(3,4-dichlorophenyl)-propionylamino]-thiazole-5-carboxylic acid (210 mg, 22%) as a white solid: mp 269–270° C.; FAB-HRMS m/e calcd for C18H18Cl2N2O3S (M+H)+ 413.0493, found 413.0483.

Provenance & Evidence