Synthesis of New bis-Iminocoumarins by Schmidt Reaction Catalyzed by Ion-Exchange Resins

Abstract

A new synthetic route to bis-iminocoumarins is proposed which involves the synthesis of iminocoumarins from reaction of 2-hydroxybenzaldehydes with arylacetonitriles and their coupling with aromatic diamines. Ion-exchange resins were used as catalysts in both steps of this synthesis. The reaction parameters were varied and obtained using Amberlyst 15 resin in cyclohexane at 80°C.     

Novel Synthesis of 2‐Oxo‐2H‐Benzopyrano[2,3‐d]Pyrimidines

Abstract

The synthesis of novel substituted 3‐cyanoiminocoumarins and corresponding N‐ethoxycarbonyl iminocoumarins is described. The condensation of N‐ethoxycarbonyl‐3‐cyano‐7‐diethylamino iminocoumarin with amines as N‐nucleophiles yields substituted 2‐oxo‐2H‐benzopyrano‐[2,3‐d]pyrimidines having promising optical properties.     

Synthesis of new iminocoumarins and their transformations into N-chloro and hydrazono compounds

The Knoevenagel reaction between 2-hydroxybenzaldehydes and active methylene compounds (malononitrile and ethyl cyanoacetate) produces iminocoumarins and/or coumarins. In order to study the reactivity of the prepared iminocoumarins, chlorination and reaction with N-nucleophiles were studied.     

Activated nitriles in heterocyclic synthesis: Synthesis of several new coumarin derivatives

Several new benzopyran and benzopyranopyridine derivatives were synthesized via condensation of 2-amino-1,1,3-tricyanopropene (1) and diethyl 2-amino-1-cyanopropene-1,3-dicarboxylate (2) with salicylaldehyde and treatment of the resulted products with active methylene regents. The spectroscopic data of the synthesized compounds are reported and discussed.

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Aktivierte Nitrile in der Heterocyclen-Synthese: Darstellung einiger neuer Cumarinderivate

Zusammenfassung Einige neue Benzopyran- und Benzopyranopyridin-derivate wurden durch Kondensation von 2-Amino-1,1,3-tricyanopropen (1) und 2-Amino-1-cyanopropen-1,3-dicarbonsäuredimethylester (2) mit Salicylaldehyd und Behandlung der Reaktionsprodukte mit aktiven Methylenreagenzien dargestellt. Die spektroskopischen Daten der neuen Verbindungen werden diskutiert.