In summary, we have described, the first time use of metallophthalocyanines
as recyclable heterogeneous catalysts for the
synthesis of 3,4-dihydropyrimidinones in refluxing acetonitrile.
The simplicity of the system, easy separation of catalyst and
products from the reaction mixture, high yields, shorter reaction
times make this an improved protocol than existing methods.
Further metal phalocyanine catalysts are easily accessible, cheap
and can be easily recovered and reused without loss in their
activities. Therefore, the use of metal phthalocyanines as catalysts
not only makes the process economical viable but also help
to reduce environmental pollution to achieve environmentally
friendly processes. Another important aspect of the present procedure
is that the other functional groups like OH, OMe, double
bonds remain intact under the described reaction conditions.