Synthesis of some novel bis (heterocycles) utilizing bis (difunctional) compounds as precursors / Soad Kamal Salama Arafat ; Supervised Ahmed Helmy Mahmoud Elwahy , Ismail Abdelshafy Abdelhamid , Ahmad Fathy Darweesh

Thesis (M.Sc.) - Cairo University - Faculty of Science - Department of Organic Chemistry

A simple, efficient and ecofriendly procedure has been developed for the synthesis of bis(4H-chromene-3-carbonitrile) derivatives using chitosan as catalyst under microwave-assisted reaction conditions. For the sake of comparison, the reaction was also carried out under conventional heating in the presence of each of chitosan and piperidine as basic catalysts. An efficient and convenient route for the synthesis of novel bis(1,4-dihydropyrano[2,3-c]pyrazole-5-carbonitrile) and bis(5,7-diamino-3-methyl- 1,4-dihydropyrazolo[4',3':5,6]pyrano[2,3-b]pyridine-6-carbonitrile) were reported. The synthetic pathway involves one pot multi-component reaction of bis-aldehydes, malononitrile or dimer malononitrile, and pyrazolone in the presence of Piperidine/EtOH.A stepwise approach for the synthesis of the target compounds was also investigated. The structures of all compounds are confirmed based on the different spectral tools

Issued also as CD