Non-covalent immobilized sultone based protic ionic liquids on nano silica sulfuric acid as novel heterogeneous catalysts for the efficient synthesis of tetrazolopyrimidines

Abstract

In this research work, a novel strategy for the heterogenization of sultone based acidic ionic liquids via their non-covalent immobilization on nano silica sulfuric acid is reported and the catalytic ability of the prepared heterogeneous catalysts for the synthesis of tetrazolopyrimidines derivatives is investigated.The physicochemical properties of the prepared catalysts were studied using thermal and spectroscopic techniques such as 1 H and 13 C NMR, FTIR, SEM, TEM, TGA, EDX and BET. In the following, tetrazolopyrimidine derivatives were synthesized in the presence of the prepared heterogeneous supported acidic ionic liquids on nano silica sulfuric acid in a three-component reaction of aromatic aldehydes, 5-aminotetrazole and active methylene compounds. The obtained results showed that the supported protic ionic liquids have better catalytic activity than their non-supported forms. Moreover, the recoverability, reusability and thermal stability of the acidic ionic liquids were also signi cantly improved by immobilization on nano silica sulfuric acid.

Recent Advances in the Multicomponent Synthesis of Heterocycles Using 5-Aminotetrazole

“…Immobilization of nano-silica sulfuric acid also enhances the recoverability, reusability, and thermal stability of the acidic ionic liquid. 99…”

“…Immobilization of nano-silica sulfuric acid also enhances the recoverability, reusability, and thermal stability of the acidic ionic liquid. 99 One-pot protocols in combination with multiple bondforming cascade transformations are highly useful and practical tools in organic and pharmaceutical synthesis. The versatility and ease of use of 10-camphorsulfonic acid (10-CSA) has made it one of the most popular organocatalysts in recent years.…”