Acetic Anhydride → N-{6-phenoxy-3-[1-(tetrahydro-pyran-4-yl)-pent-4-enyl]-quinolin-2-yl}-acetamide

To a stirred solution of the solid isolated in Step D (5.08 g, 17.6 mmol) in acetic anhydride (20 mL), sulfuric acid (1 drop) was added. The reaction mixture was stirred at room temperature for four hours. The reaction mixture was then concentrated to yield a residue. The residue was dissolved in ethyl acetate (300 mL). The resulting solution was extracted with sodium hydroxide (1.0 N) solution twice, hydrochloric acid (1.0 N) once, and brine once, and then was dried over magnesium sulfate. The solution was filtered and concentrated to yield N-{6-phenoxy-3-[1-(tetrahydro-pyran-4-yl)-pent-4-enyl]-quinolin-2-yl}-acetamide as a yellow solid.