Potassium Iodide → Hydrochloric Acid

Participants

Reaction Steps

To a suspension of 1.73 g. of trans 4-(p-fluoro-o-tolyl)cyclohexylamine hydrochloride (I) (prepared as in Example 51) in 40 ml. of dimethylformamide, 0.31 g. of 56% sodium hydride in mineral oil is added. After about 1 hour of stirring, 2 g. of potassium, 1.2 g. of potassium iodide and 1.82 g. of the 2,2-dimethyl-1,3-propanediol ketal of 4-chloro-4'-fluorobutyrophenone are added successively. The mixture is stirred in an oil bath at about 90° C. for about 18 hours, allowed to cool and the solvent removed under vacuum by a rotary evaporator. The residue is dissolved in benzene and water; the organic layer is washed with water and brine and then taken to dryness. The residue is dissolved in 30 ml. of methanol, 15 ml. of 2.5N hydrochloric acid is added and the mixture stirred for about 1 hour, then concentrated under vacuum. The precipitated solid is collected on a filter and on recrystallization from methanol:2.5N hydrochloric acid gives pure trans 4'-fluoro-4-{[4-(p-fluoro-o-tolyl)cyclohexyl]amino}butyrophenone hydrochloride (I) melting at 215° to 218° C.

Provenance & Evidence