Chemical and biological reactivity of newly synthesized 2-chloro-6-ethoxy -4-acetylpyridine

ABSTRACT

Alpha, Beta UNSATURATED ketones are very important compounds for their high reactivity usefulness in organic synthesis as key starting materials to form various classes of biologically active compounds[1-4]. As far as we know, reported investigations dealing with the use of alpha, beta - unsaturated ketones incorporating two heterocyclic moieties[1-3] were not extended to substituted pyridine in this connection-, 2,6- dichloroisonicotinic acid l[5] was selected to undertake this course of investigation, due to the broad spectrum biological features[6-9] of its derivatives. The acetyl derivative of 1 required for the synthesis of the designed 4-cinnamoyl pyridines was obtained by Claisen- condensation of ethyl ester of 1 with ethyl acetate in the presence of sodium ethoxide. The reaction was undertaken under the same conditions described by Barrus and Powell[10] followed by cleavage of the condensation product 2 with sulfuric acid to afford 2-chloro -6- ethoxy -4-acetylpyridine 4 in 45 percent yield. An unexpected product, identified as, 2-chloro -6-ethoxy -4- pyridinecarboxylic acid 3[11] was isolated, along with product 4. The Structure of 4 was furnished according to its elemental and spectral features. Formation of 3 could be attributed to partial hydrolysis of 2