Synthesis, Characterization and DFT-D Studies of 2-Aminoethoxycalix[4]resorcinarenes: A Novel Heterogeneous Organocatalyst

Abstract

The present article reports the synthesis of two novel supramolecular architectures, Phenyl(octa-2-aminoethoxy)calix[4]resorcinarene and 2-Aminoethoxyphenyl-(octa-2-aminoethoxy)calix[4]resorcinarene via surface functionalization and describes their application as heterogeneous organocatalyst in the synthesis of benzoxazole derivatives. The supramolecular structure with cavities and the presence of multiple catalytic sites in the framework enhanced the catalytic activity via co-operative effect. The newly synthesised resorcinarene frameworks were properly characterized and the thermal decomposition behaviour was studied using TG/DTG analysis which indicated that the synthesised resorcinarene derivatives possessed exceptional thermal stability. Theoretical studies using DFT-D method revealed that the newly synthesised supramolecules can exist in two different conformations, particularly in chair and twisted boat conformation. This is the first reported work where the resorcinarene based supramolecular architectures are used as heterogeneous organocatalysts for the synthesis of benzoxazole derivatives.