Eli Ranes

The cyclisation of a nitramine, formation of 3-nitropyridine from 5-nitraminopenta-2,4-dienal

Abstract On reaction of the sodium salt of 5-nitraminopenta-2,4-dienal ( 2 ) with sodium bisulfite at pH 4, 3-nitropyridine ( 10 ) was formed. Two reaction paths appeared possible for this reaction. From a 1 H NMR study of the reaction a route by the N -nitropyridinium ion 1 (Route A, Scheme 1) appeared likely. The results from the reaction of 1 under the same conditions supported this.

The reaction of 3-nitropyridine with sulfite ions; a pathway to 2,5-disubstituted pyridines

The reaction of 3-nitropyridine with an aqueous solution of sodium sulfite gave the disodium salt of 5-(N-sulfohydroxyamino)pyridine-2-sulfonic acid (2) which on treatment with an acidic ion exchange resin gave 5-hydroxyaminopyridine-2-sulfonic acid (3). The yield of 3 from 3-nitropyridine was 63%. The structures of the products were verified by X-ray analysis.