Pathilon,Burroughs-Wellcome,US,1955
Acetophenone, paraformaldehyde and diethylamine are first reacted to give ω-
diethylaminopropiophenone. That is reacted with cyclohexylmagnesium
bromide to give 3-diethylamino-1-cyclohexyl-1-phenylpropanol-1.
To 1,320 parts of methyl isobutyl ketone is added 570 parts of 3-
diethylamino-1-cyclohexyl-1-phenylpropanol-1 (2 mols) and the mixture is
stirred until solution is complete. Then 500 parts (3.2 molsor 60% excess) of
ethyl iodide are added. After filtration, the filtrate is diluted with an additional
300 parts of methyl isobutyl ketone and the solution is then heated at the
reflux temperature (108°C to 110°C) for 9 hours. After cooling to 0°C, the
precipitated solid material is removed by filtration, washed with isopropyl
acetate and dried. Approximately 777 parts of product is obtained or a yield of 88.6% based on as-is starting material or 92.5% based on real starting
material.
