Asian Journal of Research in Chemistry

The Knoevenagel condensation is a kind of nucleophilic addition reaction which is used to convert an aldehyde or ketone and an activated methylene to a substituted olefin using an amine base as a catalyst. The reaction begins by deprotonation of the activated methylene by the base to give a resonance stabilized enolate. The amine catalyst also reacts with the aldehyde or ketone to form an iminium ion intermediate, which then gets attacked by the enolate. The intermediate compound formed gets deprotonated by the base to give another enolate while the amine of the intermediate gets protonated. A rearrangement then ensues which releases the amine base, regenerates the catalyst, and yields the final olefin product. In present papera versatile function of malononitrile in the development of organic synthesis and their new result are explored. The active methylene group of malononitriles is very important attacking part in the heterocyclic conversions and also having a great influence towards several antimicrobial Activities.