To a stirred solution of 8-chloro-10,11-dihydro-dibenz[b,f][1,4]oxazepin-11-one (0.3 g; 1.22 mmol) in dry toluene (10 mL) at room temperature was added 1-benzyl piperazine (1.0 mL; 5.61 mmol; Aldrich) followed by the dropwise addition of TiCl4 (1M in toluene, 1.47 mL; 1.47 mmol). The reaction mixture was refluxed for 2 hours, cooled to room temperature and then poured into an ammonium hydroxide solution (30%, 50 mL). The resulting mixture was extracted with dichloromethane (4×50 mL), and the combined organic phases were then dried (K2CO3) and concentrated. Purification of the product was conducted on silica gel using ethyl acetate:hexane (5:1→4:1) as the eluant to give 0.471 g (95%) of the title compound as a yellow solid; m.p. 50°-52° C.
