Sulfuric Acid → 1,8-Naphthyridin-2(1H)-one

Participants

Reaction Steps

The 2-amino-1,8-naphthyridine (III) thus produced is converted to the diazonium salt with sodium nitrite in an acid, preferably trifluoroacetic acid or sulfuric acid. The diazonium salt is prepared at -5° C. or less during the addition, over a period of about 2 hours, of the sodium nitrite. The reaction mixture then is generally maintained at this temperature for an additional hour, and combined with a mixture of ice and water. The aqueous mixture is then made alkaline preferably with ammonium hydroxide, and the product 1,8-naphthyridine-2-(1H)-one (IV) isolated using known techniques.

Provenance & Evidence