Potassium Iodide → Haloperidol hydrochloride

Participants

Reaction Steps

Under a nitrogen atmosphere 4.87 parts of 4-(4-chlorophenyl)piperidin-4-ol, 1.91 parts of potassium iodide and 25 parts of deionized water is combined and gently warmed. 1.65 Parts of potassium hydroxide, followed by 6.12 parts of 1,1-ethylenedioxy-1-(4-fluorophenyl)-4-chlorobutane is added, and the mixture is heated to reflux. After refluxing for 3.75 hours, the reaction mixture is cooled to room temperature, and 55 parts of toluene is added. The aqueous and organic layers are separated, and the aqueous layer discarded. 5.1 Parts of methanol is added to the organic layer and the mixture cooled to about 25° C. While stirring vigorously, 3.1 parts of concentrated hydrochloric acid is added. The resultant precipitate is filtered and washed twice with 22 parts by volume portions of a 10:9:1 mixture of acetone-toluene-methanol. The filtrate, after standing for about 18 hours, affords additional precipitate. This is filtered and combined with the initially isolated precipitate. The solid is then washed twice with 22 parts by volume portions of a 10:9:1 mixture of acetone-toluene-methanol and twice with 22 parts by volume portions of a 10:1 mixture of acetone-methanol. The solid is air-dried to give, in 75.5% yield, 4-[4-(4-chlorophenyl)-4-hydroxypiperidino]-4'-fluorobutyrophenone hydrochloride as a white solid melting at about 226° - 228° C., and identical to the product of Example 2.

Provenance & Evidence