새롭고 효과적인 촉매로서의 메조포러스 분자체인 MCM- 41을 사용한 빠른 Knoevenagel 축합반응

Abstract

The synthesis of arylidene derivatives has attracted considerable attention from organic chemists for many years, because many of them have significant biological activity. More over, benzylidene malononitriles were reported to be effective anti-fouling agents, ungicides and insecticides. They are important intermediates for the synthesis of various organic compounds. Knoevenagel condensation of carbonyl compounds on molecules containing an active methylene group is an important method for the preparation of substituted alkenes. Several important key products, such as nitriles used in anionic polymerization and a,b-unsaturated ester intermediates employed in the synthesis of several therapeutic drugs, e.g., niphedipine and nitrendipine, etc have been synthesized via this condensation. Ylidenenitriles have increasing applications in industry, medicine, agriculture and biological science, and are precursors to heterocycles. The reaction is catalyzed by primary and secondary amines or their corresponding ammonium salts in harmful solvents or with Lewis acids, as TiCl 4 / base, ZnCl 4 , CdI 2 4c and other catalysts. Most of these methods have not been entirely satisfactory owing to such drawbacks as low yields, long reaction times and effluent pollution. In continuation of our program to develop reactions in eco-friendly conditions and our interest in the Knoevenagel reaction, in this communication we wish to disclose our results for this reaction using MCM-41 as catalyst.