Trifluoroacetic acid → E-1210

Participants

Reaction Steps

To a dichloromethane (120 mL) solution of di-tert-butyl (3-(3-(4-((pyridin-2-yloxy)methyl)benzyl)isoxazol-5-yl)pyridin-2-yl)imidodicarbonate (11.8 g, purity about 70%) described in Manufacturing Example 1-4-2 was added trifluoracetic acid (40 mL) at 0° C., which was stirred at room temperature for 14 hours. To the reaction mixture was added saturated aqueous sodium bicarbonate at 20° C. or less, which was then extracted with ethyl acetate and purified by NH silica gel column chromatography (heptane:ethyl acetate=1:1). The solvent was concentrated under a reduced pressure, tert-butylmethyl ether was added to the resulting residue, and the solids were filtered to obtain the title compound (7.29 g).

Provenance & Evidence