Green heterogeneous catalysis: chitosan and nanoparticulated magnesium oxide as ecofriendly catalyses for michael addition

Heterogeneous ecofriendly base catalysis namely, chitosan and naoparticulated MgO are promising new catalysis in Michael addition that can efficiency replace homogeneous polluting catalysts. Aminopyrancarbonitriles, pyranopyrazole, thiazologyridines and chromenes can be obtained in ethanolic or methanolic chitosan or MgO in good yields