Hantzsch reaction: The important key for pyridine/dihydropyridine synthesis
Md Imam Faizan, Rajnish Kumar, Avijit Mazumder, Salahuddin Salahuddin, Neelima Kukreti, Pankaj Tyagi, Bhupinder Kapoor
Abstract
Pyridines and its derivatives are an important class of heterocyclic compounds of low molecular weight. They have been used in the treatment of a various diseases like cardiovascular disease, antioxidant, antibacterial, anti-tubercular, anticancer, anticoagulant, etc. In 1882, Arthur Hantzsch reported pyridine derivative synthesis using different aldehydes, 2 molecules β-keto ester and ammonium acetate to give a Hantzsch ester or 1,4-dihydropyridine derivatives. This review article focuses on different protocols for Hantzsch reaction using different catalysts like β-cyclodextrin–polyurethane polymer (β-CDPU), chitosan nanoparticles (NPs), salicylic acid, p-toluenesulfonic acid (p-TSA), alginic acid, Fe-TUD-1, PdRuNi@GO, Ceric Ammonium Nitrate (CAN), sulfate polyborate, etc. for the synthesis of pyridine derivatives.