合成路线1

Mannich reaction of 6,7-dimethyltetralone (I) with dimethylamine and formaldehyde provided amino ketone (II). Subsequent quaternization of (II) with MeI in acetone gave ammonium salt (III), that was further displaced by KCN yielding nitrile (IV). Acidic hydrolysis of the cyano group of (IV) produced carboxylic acid (V). This was then coupled with pyrrolidine (VI) employing BOP reagent to furnish amide (VII). Reduction of the ketone and amide functions of (VII) by means of vitride?in toluene afforded amino alcohol (VIII). After alcohol (VIII) dehydration with ethanolic HCl, the title compound was isolated as the fumarate salt.