A solution of 28.2 g (0.2 mol) of 3-tropanol is prepared in 50 ml of xylol, and
to this solution is added 23.8 g (0.1 mol) of 4-chlorobenzhydryl chloride. The
resultant solution is heated for 7 h at 145°-155°C, following which the
mixture is cooled and filtered. The clear filtrate thus obtained is washed with
50 ml of 5% aqueous potassium carbonate solution and then with three
successive 25 ml portion of water. The xylol solution is then extracted with
three successive 50 ml portions of 2 N hydrochloric acid. The xylol layer is
discarded and the acid extracts are combined and rendered strongly basic by
the addition of 22.5% aqueous potassium hydroxide, resulting in the
formation of an oily base which separates and which is then extracted with
benzol, from which the benzol is evaporated to yield crude 3-(4'-
chlorobenzhydryloxy)tropane as a brown oil.
2.0 g of 3-(4'-chlorobenzhydryloxy)tropane is treated with 10 ml of 4.5 N
isopropanoic acid hydrogen chloride solution, and the pasty mixture which
results is diluted with approximately 30 ml of absolute ether. A solid product is
formed which is separated by filtration and then washed with absolute ether.
The product is then purified by dissolving it in hot isopropanol, followed by
clarification with activated charcoal. Upon cooling the filtrate, the 3-(4'-
chlorophenylbenzyloxy)tropane separates as a crystalline powder, melting
point 215°-217°C.
In practice it is usually used as hydrochloride.
