Sodium Hydroxide → HCID 70045569, compound

Participants

Reaction Steps

A solution containing 30 g (0.08 mole) of 2-[3-(benzo[1,4]dioxan-2-yl-methylamino)-1-propyl]-6-chloro-3(2H)-pyridazinone hydrochloride (prepared as described in Example 2), 600 ml of absolute ethanol and 6.2 g of powdered sodium hydroxide is hydrogenated in the presence of 3 g of 5% palladium-on-charcoal catalyst under atmospheric pressure and at room temperature. After ceasing of the hydrogen uptake, the catalyst is filtered off, washed 3 times with 20 ml of absolute ethanol each and the filtrate is evaporated under reduced pressure. The residue is boiled with 50 ml of absolute isopropanol for 5 minutes and then filtered. The pH value of the filtrate is adjusted to 4 by adding 25% ethanolic hydrogen chloride solution under stirring and cooling with ice. The mixture is kept at 4° C. overnight, the crystalline precipitate is filtered off, washed with ice-cool absolute ethanol and dried to give 17 g (63% yield) of the aimed product, m. p. 131°-132° C. After recrystallization from ethanol, the hydrochloride melts at 133°-136° C.

Provenance & Evidence