A novel, efficient, and recyclable biocatalyst for Michael addition reactions and its iron(iii) complex as promoter for alkyl oxidation reactions

Abstract

Chitosan-g-poly(2-cyano-1-(pyridin-3-yl)allyl acrylate) (Cs-g-PCPA), having a grafting percentage (G%) of 64%, was prepared and was then subjected to complexation with iron(III) (Cs-g-PCPA/Fe(III)). The results of the catalytic studies demonstrated that Cs-g-PCPA serves as an efficient, recyclable and eco-friendly, basic catalyst for Michael addition reactions, which produce adducts in high yields under mild conditions. Moreover, a Cs-g-PCPA-supported iron(III) complex was prepared and was then characterized by using FESEM, XRD, TGA, and XPS. In addition, the EDS plot of the Fe(III) chelate confirms the presence of a relatively high amount (13%) of Fe(III). The Cs-g-PCPA (G% = 64)-supported iron(III) complex (Cs-g-PCPA/Fe(III)) in the presence of H₂O₂ can be used to oxidize methyl pyridazinyl carbonitriles to form the corresponding fused furan derivatives efficiently. These polymeric catalysts are stable such that they can be recycled and reused more than five times without losing their catalytic activity.