Silica sulfuric acid as mild and efficient catalyst for the preparation of poly-hydroxyl aromatic compounds under mild and heterogeneous conditions

Solvent-free synthesis of trisphenols as starting precursors for the synthesis of calix[4]arenes using sulfonated multi-walled carbon nanotubes

The condensation of phenol derivatives with 2,6-bis(hydroxymethyl)phenols is reported using SO₃H@MWCNTs under solvent-free conditions as precursors for the synthesis of calix[4]arenes.