Formic Acid → HCID 22712051, compound

Participants

Reaction Conditions

Reaction Steps

The base is liberated from 47.4 g of 1-benzyl-4-(3-hydroxypropylamino)-piperidine-dihydrochloride, combined with 63 ml of 85% formic acid and 22 ml of 37% formaldehyde solution and stirred for two hours at about 90-100° C. The mixture is left to cool, 37 ml of formic acid and 11 ml of formaldehyde solution are added and stirred for another hour at about 100-110° C. The mixture is left to cool, combined with 150 ml of methanol, made alkaline with about 270 ml of 32% sodium hydroxide solution while cooling and stirred for about another 30 minutes at 40-50° C. and the methanol is then distilled off. The residue is extracted with twice 100 ml of methylene chloride, the combined methylene chloride phases are dried, filtered and the solvent is eliminated in vacuo. The residue is taken up in 80 ml of ethanol, acidified with 34 ml of 32% hydrochloric acid, combined with 100 ml of acetone and stirred. As soon as crystals are precipitated, further acetone is added. The precipitate is suction filtered, washed with acetone and dried. 42.8 g of 1-benzyl-4-[-(3-hydroxypropyl)-methylamino]-piperidine-dihydrochloride are obtained as a solid.

Provenance & Evidence