Sulfonated Honeycomb Coral (HC-SO3H): a new, green and highly efficient heterogeneous catalyst for the rapid one-pot pseudo-five component synthesis of 4,4'-(aryl methylene) bis(3-methyl-1H-pyrazol-5-ol)s

Sulfonated Honeycomb Coral (HC-SO3H), has been synthesized from the reaction of Honeycomb Coral with chlorosulfonic acid as sulfonating agent. The as-synthesized catalyst was characterized via XRF, FT-IR, TGA, SEM-EDS, XRD, BET and pH analysis. The superior catalytic activity of HC-SO3H was investigated for the synthesis of 4,4'-(aryl methylene)bis(3-methyl-1H-pyrazol-5-ol) derivatives through the one-pot pseudo-five component reactions. The main advantages of this protocol include simple procedure, excellent yields and short reaction times besides the non-toxicity, high stability and reusability of the catalyst.