Mesoporous SBA-15/PIDA as a Dendrimer Zwitterionic Amino Acid-Type Organocatalyst for Three-Component Indazolophtalazine Synthesis

A zwitterionic amino acid-like N-propyliminodiacetic acid (PIDA) organocatalyst supported to a heterogeneous surface (SBA-15/PIDA) based on iminodiacetic acid and mesoporous SBA-15, respectively was synthesized. The mesoporous hybrid catalyst was successfully characterized by SEM, TEM, TGA, FTIR, and EDS and employed in the three-component reaction of dimedone, aldehydes and phtalhydrazide for the synthesis of indazolophtalazinetrione. SBA-15/PIDA exhibited excellent catalytic activity in the reaction and showed highly recyclable and recoverable features in consecutive reaction runs. According to ab initio calculations, the recoverability of SBA-15/PIDA catalyst is attributed to the strong covalent bonding between PIDA and SBA-15. Graphical Abstract: [Figure not available: see fulltext.]. © 2019, Springer Science+Business Media, LLC, part of Springer Nature.