Hydrochloric Acid → HCID 14459487, compound

Participants

Reaction Conditions

Reaction Steps

An ice cold solution of 0.9 g (8.5 mmol) of sodium nitrite in 5 ml of water is added dropwise over a period of 10 minutes to a solution of 3.0 g (8.3 mmol) of 6-[3-amino-4-(4-ethoxycarbonylpiperazin-1-yl)-phenyl]-4,5-dihydro-5-methyl-3(2H)-pyridazinone in 7 ml of conc. hydrochloric acid and 3 ml of water at -5° C. The resulting reaction mixture is then added to a solution of 1.29 g (13 mmol) of copper-(I) chloride in 5 ml of conc. hydrochloric acid which is at 0° C. When evolution of gas has ceased, the solution is slowly heated to 50° C. and then cooled and adjusted to pH 11 with potassium carbonate. The aqueous phase is extracted three times with 50 ml of dichloromethane and the organic phases are dried, filtered and concentrated by evaporation under vacuum. The residue obtained is chromatographed on silica gel with dichloromethane/methanol (95:5) and after concentration of the lipophilic main fraction under vacuum it yields 1.2 g (38%) of a colourless solid, m.p. 154°-156° C.

Provenance & Evidence