Synthesis of calixresorcarenes using magnetic poly triazine-benzene sulfonamide-SO3H

Abstract

The purpose of this work is to develop a magnetically recyclable immobilized base catalyst for the green synthesis of calixresorcarenes. To achieve this, poly triazine-benzene sulfonamide (PTBSA) has been coated on magnetic Fe₃O₄ nanoparticles and subsequently chlorosulfonic acid has been supported to obtain Fe₃O₄@PTBSA-SO₃H. The structure of nano-Fe₃O₄@PTBSA-SO₃H was characterized by TEM, XRD, FT-IR, VSM, WDX, EDX, TGA/DSC and FE-SEM. The catalytic efficiency of this catalyst was also investigated in the synthesis of novel calixresorcarene derivatives. The advantages of heterogeneous nature, catalytic activity and the recyclability of the polymer support were also strengthened by advanced surface treatment. These key factors (basic sites, acidic sites and heterogeneity) play essential roles in the catalyst performance. This procedure has some advantages such as short reaction time, clean and fast work-up and easy separation of the catalyst by an external magnet.