2-Aminothiazole → (E)-2-[3-chloro-4-(5-trifluoromethyl-tetrazol-1-yl)-phenyl]-3-cyclohexyl-N-thiazol-2-yl-acrylamide

Participants

Reaction Conditions

Reaction Steps

A solution of triphenylphosphine (772 mg, 2.96 mmol) in methylene chloride (10 mL) was cooled to 0° C. and then treated with N-bromosuccinimide (526 mg, 2.96 mmol). The reaction mixture was stirred at 0° C. for 30 min and then treated with a solution of (E)-2-[3-chloro-4-(5-trifluoromethyl-tetrazol-1-yl)-phenyl]-3-cyclohexyl-acrylic acid (594 mg, 1.48 mmol) in methylene chloride (5 mL). The reaction mixture was then stirred for 15 min at 0° C. and then allowed to warm to 25° C. where it was stirred for 1.5 h. The reaction mixture was then treated with 2-aminothiazole (444 mg, 4.44 mmol), and the resulting suspension was stirred for 2 d at 25° C. The reaction mixture was concentrated in vacuo to remove methylene chloride, and the residue was diluted with ethyl acetate (70 mL) and a 1N aqueous hydrochloric acid solution (50 mL). The two layers were separated, and the aqueous layer was extracted with ethyl acetate (1×50 mL). The combined organic extracts were successively washed with a 1N aqueous hydrochloric acid solution (1×100 mL), a saturated aqueous sodium bicarbonate solution (1×100 mL) and a saturated aqueous sodium chloride solution (1×100 mL), dried over anhydrous magnesium sulfate, filtered, and concentrated in vacuo. Biotage chromatography (FLASH 40S, Silica, 5/1 to 3/2 hexanes/ethyl acetate) afforded (E)-2-[3-chloro-4-(5-trifluoromethyl-tetrazol-1-yl)-phenyl]-3-cyclohexyl-N-thiazol-2-yl-acrylamide (82 mg, 11%) as an amorphous solid: EI-HRMS m/e calcd for C20H18ClF3N6OS (M+) 482.0903, found 482.0906.

Provenance & Evidence