Hydrochloric Acid → Doxepin

Participants

Reaction Steps

5.4 g (0.02 mol) of the 11-(3-chloropropylidene)-6,11-dihydrodibenzo-[b,e]-oxepine, prepared according to (c) above, in 20 mL tetrahydrofuran and 5.5 g (0.12 mol) dimethylamine in 20 mL ethanol is heated together for 3 hours using a glass autoclave and a temperature of 95-100° C. (boiling water bath). Water and 6 N hydrochloric acid are added to the contents of the autoclave and the mixture is extracted with ether. The separated, aqueous-acid components are then made alkaline with dilute caustic soda solution, and the oil thereby separated is taken up in ether. The ether residue, after distillation in a high vacuum, produces 4.1 g (73.5% of theory) of 11-(3-dimethylamino-propylidene)-6,11-dihydrodibenzo-[b,e]-oxepine, having a B.P.0.1 147-150° C. The melting point of the hydrochloride is 182-184° C. (recrystallized from isopropanol).

Provenance & Evidence