Facile and green synthesis of novel compounds tetrakis([1,3] oxazine) calix[4]resorcinarenes via the Mannich reaction with ion exchanger V as a highly efficient and environmentally Safe catalyst

Abstract

In this study, we introduce a pioneering methodology distinguished by its remarkable simplicity and efficiency for the synthesis of macrocycles based on resorcinarene. Specifically, we achieved the synthesis of tetrakis([1,3] oxazine) calix[4]resorcinarenes through the Mannich reaction involving resorcin[4]arenes, formaldehyde, and cyclohexylamine. Notably, the utilization of ion exchanger V as a catalyst emerged as an economically viable and environmentally sustainable choice. Ion exchanger V stands out for its styrene polymer chain, housing highly active functional groups and offering a generous surface area, thus enhancing its catalytic prowess. This catalytic system confers numerous advantages, including streamlined synthesis procedures, reduced reaction durations, uncomplicated purification methodologies, and outstanding product yields. The structural characterization of the synthesized compounds was meticulously conducted through Fourier-transform infrared spectroscopy (FT-IR) and solid-state nuclear magnetic resonance (SSNMR) techniques, and High-resolution mass spectrometry (HR-MS) conclusively affirming the authenticity and integrity of the target molecules. © 2024 Elsevier B.V., All rights reserved.