Hydrochloric Acid → 4-({[tert-Butyl(diphenyl)silyl]oxy}methyl)-2-(piperidin-4-yloxy)-6-(trifluoromethyl)pyridine

Participants

Reaction Steps

To a solution of tert-butyl 4-{[4-({[tert-butyl(diphenyl)silyl]oxy}methyl)-6-(trifluoromethyl)pyridin-2-yl]oxy}piperidine-1-carboxylate (0.19 g, 0.23 mmol, from Step B) in 1,4-dioxane (2.0 mL) was added 4.0M hydrogen chloride in dioxane (0.50 mL, 2.0 mmol). The reaction mixture was stirred for one hour. Additional 4.0M hydrogen chloride in dioxane (0.50 mL, 2.0 mmol) was added and stirring was continued for two hours. The mixture was diluted with water, saturated sodium bicarbonate was used to adjust the pH to between 7 and 8, and then the product was extracted with two portions of DCM. The combined extracts were washed with brine, dried over sodium sulfate, filtered and concentrated. Flash chromatography on silica gel, eluting with a gradient from 0-15% MeOH in DCM afforded product as an oil (62 mg, 52%). 1H NMR (400 MHz, CDCl3) δ 7.69-7.62 (m, 4H), 7.48-7.34 (m, 6H), 7.14-7.11 (m, 1H), 6.91 (s, 1H), 5.17 (tt, J=8.7, 4.0 Hz, 1H), 4.71 (s, 2H), 3.13 (dt, J=12.7, 4.5 Hz, 2H), 2.78 (ddd, J=12.7, 9.7, 3.0 Hz, 2H), 2.07 (dq, J=12.2, 4.1 Hz, 2H), 1.67 (dtd, J=13.0, 9.4, 3.9 Hz, 2H), 1.11 (s, 9H); LCMS (M+H)+: 515.2.

Provenance & Evidence