A powerful new one-pot method has been developed for the reductive alkylation of malononitrile with aromatic aldehydes. This new procedure has vastly improved the yield and efficiency and increased the scope for the aromatic aldehydes. Incorporating water as the catalyst in ethanol for the condensation step allows stoichiometric amounts of malononitrile and aldehyde to be employed. After dilution and cooling the reduction step takes place quickly and efficiently with sodium borohydride to give monosubstituted malononitriles.The product from the reductive alkylation of malononitrile with 2-quinolinecarboxaldehyde quickly rearranges to a novel indolizine on silica gel or with heat, while alkylation of the monosubstituted derivative provides an unsymmetrically disubstituted malononitrile.We have also investigated this improved one-pot reductive alkylation using various 2-hydroxybenzaldehydes where intramolecular cyclization occurs following the condensation step and various 2-amino-3-cyano-4H-chromenes are formed. / Department of Chemistry
| Identifer | oai:union.ndltd.org:BSU/oai:cardinalscholar.bsu.edu:handle/188442 |
| Date | January 2008 |
| Creators | Tayyari, Fariba |
| Contributors | Sammelson, Robert E. |
| Source Sets | Ball State University |
| Detected Language | English |
| Format | iii, 128 leaves : ill. ; 28 cm. |
| Source | Virtual Press |
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