Originator
Cantor,Clin Midy,France,1979
Manufacturing Process
(a) Preparation of the free base: A mixture comprising 0.1 mol (20.4 g) of 3-chloro-4-methyl-6-phenylpyridazine and 0.2 mol (26.2 g) of N-(2-aminoethyl)-morpholine in 100 ml of n-butanol, with a pinch of copper powder, was heatedunder reflux for 12 hours. At the end of this time, the hot solution was pouredinto 200 ml of cold water. The resulting mixture was filtered through asintered glass filter and the precipitate washed with ether. The filtrate and theether washings were placed in a separating funnel and extracted with two 150ml portions of ether. The ethereal layer was then extracted with about 250 mlof N sulfuric acid.
The acid solution was made alkaline with a 10% aqueous solution of sodiumcarbonate, and left to crystallize overnight.
The solution was filtered, yielding the colorless needles which wererecrystallized from isopropanol. The yield was 15 g (53%).
(b) Preparation of the hydrochloride: The base was dissolved in the smallestamount possible of anhydrous acetone. Double that volume of anhydrousether was added, and a stream of hydrogen chloride gas was passed throughthe solution. The hydrochloride salt obtained was recrystallized from absolutealcohol. The yield after recrystallization was 17 g (90%).
