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Friedlaender Synthesis Yafa M’arouf Ezzat Zaqzouq Dr. Fu’ad Mahmod Table of Contents Objectives Background Reaction and Mechanism Application and recent literature Conclusion References Objectives *To understand Friedlaender synthesis. *To show the equation & the mechanism of the reaction. *To gain some knowledge about the applications & recent literatures related to the reaction. Background The Friedländer synthesis is the chemical reaction of 2-aminobenzaldehydes with ketones to form quinoline derivatives. It is named after German chemist Paul Friedländer (1857-1923). The simple and straightforward method for the synthesis of polysubstituted quinolines was reported by Friedländer in 1882. Friedländer reactions are generally carried out either by refluxing an aqueous or alcoholic solution of reactants in the presence of base or by heating a mixture of the reactants at high temperatures ranging from 150-220°C in the absence of catalyst.(1) Reaction and Mechanism Friedlaender Synthesis The starting materials for this quinoline synthesis are o-amino aryl aldehydes or ketones and a ketone possessing an α-methylene group. After an initial amino-ketone condensation, the intermediate undergoes base- or acid-catalyzed cyclocondensation to produce a quinoline derivative. (2) Mechanism of the Friedlaender Synthesis Two viable reaction mechanisms exist for this reaction. In the first mechanism 2-amino substituted carbonyl compound 1 and carbonyl compound 2 react in a rate-limiting step to aldol adduct 3. This intermediate loses water in an elimination reaction to unsaturated carbonyl compound 4 and then loses water again in imine formation to quinoline 7. In the second mechanism the first step is Schiff base formation to 5 followed by Aldol reaction to 6 and elimination to 7. (2) Application and recent literature *Rapid and efficient synthesis of poly-substituted quinolines assisted by p-toluene sulphonic acid under solvent-free conditions: (4) *Molecular iodine: a highly efficient catalyst in the synthesis of quinolines via Friedländer annulation: (4) *Transition-Metal-Free Indirect Friedländer Synthesis of Quinolines From Alcohols: (4) *Ionic Liquid-Promoted Regiospecific Friedlander Annulation: (4) Conclusion The Friedländer synthesis is the chemical reaction of 2-aminobenzaldehydes with ketones to form quinoline derivatives. This reaction has been catalyzed by trifluoroacetic acid, toluenesulfonic acid, iodine, and Lewis acids. References 1.http://chem-info.blogspot.com/2011/04/friedlaenderquinoline-synthesis.html 2.http://www.organic-chemistry.org/namedreactions/ friedlaender-synthesis.shtm 3.http://www.lookchem.com/Chempedia/BasicChemical/Chemical-Reaction/8340.html 4.http://en.wikipedia.org/wiki/Friedl%C3%A4nder_ synthesis