Dichloromethane → HCID 86718601, compound

Participants

Reaction Steps

The free base of 2-(aminomethyl)-4-(tert-butyl)-6-(6-(trifluoromethyl)pyridin-3-yl)phenol hydrochloride (Example 64), was prepared by partitioning the hydrochloride salt (560 mg, 1.55 mmol) between ethyl acetate and a saturated aqueous sodium bicarbonate solution. The organic phase was separated, dried (Na2SO4), filtered and the solvent removed under reduced pressure. The residue was redissolved in a solution of tert-butyl (2-oxopropyl)carbamate in ethanol (5 mL) and stirred for three days. Sodium borohydride (290 mg, 7.75 mmol) was added portionwise and the reaction mixture stirred at room temperature for one hour. The reaction was quenched with saturated aqueous ammonium chloride solution (1 mL) and the reaction mixture partitioned between ethyl acetate and a saturated aqueous sodium bicarbonate solution. The organic phase was separated, dried (Na2SO4), filtered and the solvent was removed under reduced pressure. The residue was purified using flash chromatography on silica eluting with a solvent gradient of 0-100% ethyl acetate in hexanes to give tert-butyl (2-((5-(tert-butyl)-2-hydroxy-3-(6-(trifluoromethyl)pyridin-3-yl)benzyl)amino)propyl)carbamate (500 mg, 67%) as a white solid. The carbamate (500 mg, 1.04 mmol) was dissolved in methylene chloride (20 mL) and trifluoroacetic acid (10 mL) added and the reaction was stirred for 16 h. The solvent was removed under reduced pressure, the residue azeotroped twice with toluene (20 mL) and then redissolved in a 1:1 mixture of methylene chloride and trifluoracetic acid (40 mL) and stirred at room temperature for four hours. The solvent was removed under reduced pressure, the residue azeotroped twice with toluene (20 mL) and the residue partitioned between ethyl acetate and saturated aqueous sodium bicarbonate solution. The organic phase was separated, dried (Na2SO4), filtered and the solvent removed under pressure. The residue was purified using flash chromatography on silica eluting with a solvent gradient of 0 to 100% of (89% methylene chloride, 10% methanol and 1% ammonium hydroxide) in methylene chloride. The purified residue was dissolved in a 1.25 M hydrochloric acid solution in ethanol, the solution stood for 10 minutes, and then the solvent removed under reduced pressure and the residue triturated with diethyl ether to give 2-(((1-aminopropan-2-yl)amino)methyl)-4-(tert-butyl)-6-(6-(trifluoromethyl)pyridin-3-yl)phenol dihydrochloride (150 mg, 32% yield) as a white solid.

Provenance & Evidence