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Guanidinylated SBA-15/Fe₃O₄ mesoporous nanocomposite as an efficient catalyst for the synthesis of pyranopyrazole derivatives.

ABSTRACT: In this study, a novel mesoporous nanocomposite was fabricated in several steps. In this regard, SBA-15 was prepared by the hydrothermal method, next it was magnetized by in-situ preparation of Fe₃O₄ MNPs. After that, the as-prepared SBA-15/Fe₃O₄ functionalized with 3-minopropyltriethoxysilane (APTES) via post-synthesis approach. Then, the guanidinylated SBA-15/Fe₃O₄ was obtained by nucleophilic addition of APTES@SBA-15/Fe₃O₄ to cyanimide. The prepared nanocomposite exhibited excellent catalytic activity in the synthesis of dihydropyrano[2,3-c]pyrazole derivatives which can be related to its physicochemical features such as strong basic sites (presented in guanidine group), Lewis acid site (presented in Fe₃O₄), high porous structure, and high surface area. The characterization of the prepared mesoporous nanocomposite was well accomplished by different techniques such as FT-IR, EDX, FESEM, TEM, VSM, TGA, XRD and BET. Furthermore, the magnetic catalyst was reused at least six consequent runs without considerable reduction in its catalytic activity.

SUBMITTER: Hassanzadeh-Afruzi F

PROVIDER: S-EPMC8494731 | biostudies-literature |

REPOSITORIES: biostudies-literature

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