%0 Journal Article
%T Rearrangement of o-Nitrobenzaldehyde in the Hantzsch Reaction
%A E. Angeles
%A H. Santill¨¢n
%A I. Menconi
%A I. Mart¨ªnez
%A A. Ram¨ªrez
%A A. Vel¨¢zquez
%A R. L¨®pez- Casta£¿ares
%A R. Mart¨ªnez
%J Molecules
%D 2001
%I MDPI AG
%R 10.3390/60800683
%X The reaction of 5-hydroxy-2-nitrobenzaldehyde with ethyl acetoacetate in ammonia gave the two expected isomeric 1,4- and 1,2-dihydropyridines resulting from the normal Hantzsch reaction. However, the combination of 2-nitrobenzaldehyde with ethyl acetoacetate under the same conditions yielded four products: the two normal isomeric dihydropyridines and two tricyclic compounds. When we attempted to independently synthesize the two tricyclic compounds by reductive cyclization of 4-(2-nitrophenyl)-2,6-dimethyl-3,5-dicarbetoxy-1,4-dihydropyridine and 2-(2-nitrophenyl)-4,6-dimethyl-3,5-dicarbetoxy-1,2-dihydropyridine with tin (II) chloride in hydrochloric acid media, we obtained instead an indole and a quinoline derivative, respectively.
%K Hantzsch reaction
%K cyclization
%K indole derivatives
%K quinoline derivatives
%U http://www.mdpi.com/1420-3049/6/8/683