12 ml of anhydrous dimethylsulfoxide were added under nitrogen to 1.2 g of sodium hydride as a 50% oil dispersion and the mixture was stirred at 60° C. for 30 minutes and was then cooled to 25° C. 4.8 g of trans 3-chloro-7-dimethylamino-6,7,8,9-tetrahydro-5H-benzocyclohepten-5-ol were added thereto and the mixture was stirred for 15 minutes at 25° C. after which 6.3 g of p-chloronitrobenzene were added thereto. The mixture was stirred for one hour and 500 ml of water were added thereto. The mixture was extracted with methylene chloride and the organic phase was dried over magnesium sulfate and was evaporated to dryness under reduced pressure. The residue was taken up in 130 ml of N hydrochloric acid and after standing for 20 minutes, the mixture was vacuum filtered. The recovered product was washed with ether, then water and dried under vacuum to obtain 7.3 g of product which was crystallized from methanol and ethyl acetate to obtain 5 g of trans N,N-dimethyl-3-chloro-5-[4-nitrophenoxy]-6,7,8,9-tetrahydro-5H-benzocyclohepten-7-amino hydrochloride in the form of colorless crystals melting at 230° C.
