Synthesis of Isatine Derivatives Considering Pfitzinger Reaction Part I

Prof. Dr. Mohammad Mahdi Saleh, Marwa Ibrahim Khaleel

Abstract: In this work neuteric quinoline-4- carboxylic acid derivatives have been compilation from isatin. Onset, quinoline -4-carboxylic derivatives were designed from the reaction of isatin with different ketone (benzophenone, acetylacetone and acetone) in presence of powerful base (KOH) under Pfitzinger reaction case to obtain corresponding derivatives (1-3). Secondly, derivatives (4-6) have prepared by reflux of compounds (1-3) with p-hydroxybenzaldehyde in presence of few drops of concentrated sulfuric acid, and then the products were refluxed respectively with guanine to give desired compounds (7-9). Furthermore, carboxamide derivatives (10-12) have been prepared by refluxing of compounds (1-3) with o-phenylenediamine (benzene-1, 2-diamine) in ethanol solvent. Finally, derivatives (16-18) have been prepared by reaction of synthesized derivatives (13-15) that prepared from the reaction of compounds (1 -3) with thionyl chloride followed by conversion into corresponding quinoline-8-yl (substituted quinoline-4- carboxylic acid (16-18) by reaction with quinolin-8-ol in acetone. All structures of newly synthesized compounds have been characterize and identified via of their physical properties and spectral data analysis (1H-NMR, FT-IR and U. V. ).

Keywords: Pfitzinger reaction, powerful base, o-phenylenediamime, quinoline-8-yl, thionyl chloride