Ammonium Chloride → 1-[1-(3-Chloro-5-trifluoromethyl-pyridin-2-yl)-cyclopropyl]-ethylamine

Participants

Reaction Conditions

Reaction Steps

412 mg of 2-methyl-propane-2-sulfinic acid 1-[1-(3-chloro-5-trifluoromethyl-pyridin-2-yl)-cyclopropyl]-methylideneamide (step 3) was dissolved in 12 ml of dichloromethane and cooled to −48° C. 0.78 ml of methylmagnesium bromide (3M solution in diethyl ether) was added dropwise at −48° C. The reaction mixture was left to warm to ambient temperature and stirred for 18 hours. Then the mixture was poured into 30 ml of a saturated aqueous ammonium chloride solution. The aqueous phase was extracted with three 30 ml portions of ethyl acetate. The organic phase was dried over sodium sulfate, filtered and concentrated. The residue was dissolved in 12 ml of methanol and 0.6 ml of hydrochloric acid (4M solution in dioxane) was added. The mixture was stirred at ambient temperature for 2 hours, then concentrated. The residue was treated with aqueous 1N hydrochloric acid and washed with ethyl acetate. The aqueous phase was made basic by addition of aqueous sodium hydroxide solution, then extracted with ethyl acetate. The organic phase dried over sodium sulfate, filtered and concentrated. Thus, 262 mg of 1-[1-(3-chloro-5-trifluoromethyl-pyridin-2-yl)-cyclopropyl]-ethylamine was obtained as a yellow oil. 1H-NMR (CDCl3): 8.72 ppm (s, 1H), 7.90 ppm (s, 1H), 3.10 ppm (q, 1H), 1.34 ppm (s, 2H, broad), 1.06 ppm (d, 3H), 1.02 ppm (m, 2H), 0.93 ppm (m, 2H).

Provenance & Evidence