Triphenylphosphine → (E)-N-(5-bromo-pyridin-2-yl)-3-cyclohexyl-2-(4-methanesulfonyl-3-trifluoromethyl-phenyl)-acrylamide

Participants

Reaction Conditions

Reaction Steps

A solution of triphenylphosphine (525 mg, 2 mmol) in methylene chloride (12 mL) was cooled to 0° C. and then treated with N-bromosuccinimide (356 mg, 2 mmol). The reaction mixture was stirred at 0° C. for 30 min and then treated with (E)-3-cyclohexyl-2-(4-(methanesulfonyl)-3-(trifluoromethyl)-phenyl)-acrylic acid (prepared in Example 12, 376 mg, 1 mmol). The reaction mixture was stirred at 25° C. for 15 min and then allowed to warm to 25° C. where it was stirred for 1.5 h. The reaction mixture was then treated with 2-amino-5-bromopyridine (519 mg, 3 mmol), and the resulting suspension was stirred for 3 d at 25° C. The reaction mixture was concentrated in vacuo to remove methylene chloride, and the residue was diluted with ethyl acetate (50 mL) and a 1N aqueous hydrochloric acid solution (50 mL). The two layers were separated, and the aqueous layer was extracted with ethyl acetate (1×30 mL). The combined organic extracts were successively washed with a saturated aqueous sodium bicarbonate solution (1×50 mL) and a saturated aqueous sodium chloride solution (1×50 mL). The organic layer was then dried over anhydrous magnesium sulfate, filtered, and concentrated in vacuo. Biotage chromatography (FLASH 40S, Silica, 4/1 to 2/1 hexanes/ethyl acetate) afforded the (E)-N-(5-bromo-pyridin-2-yl)-3-cyclohexyl-2-(4-methanesulfonyl-3-trifluoromethyl-phenyl)-acrylamide (44 mg, 8.3%) as an amorphous solid: EI-HRMS m/e calcd for C22H22BrF3N2O3S (M+) 530.0487, found 530.0484.

Provenance & Evidence