Alkylation of 2,3,4,5-tetrahydro-1,4-benzoxazepin-3,5-dione (I) with 1-bromo-4-chlorobutane (II) in the presence of K2CO3 afforded the 4-(chlorobutyl)benzoxazepindione (III), which was further treated with POCl3 in boiling dioxan to yield the 3-chlorobenzoxazepinone (IV). Condensation of (IV) with 4-(2-pyridyl)-1,2,5,6-tetrahydropyridine (V) using NaI and Et3N in hot DMF provided the target compound, which was isolated as the dihydrochloride salt.

In an alternative procedure, the chlorobutyl derivative (IV) was condensed with 2,4'-dipyridine (VI) by means of NaI in boiling acetone, yielding pyridinium salt (VII). Subsequent reduction of (VII) with NaBH4 in EtOH then provided the title tetrahydropyridine.