Sulfated polyborate: An efficient and reusable catalyst for one pot synthesis of Hantzsch 1,4-dihydropyridines derivatives using ammonium carbonate under solvent free conditions

Novel and Effective Strategy of Multifunctional Titanium Incorporated Mesoporous Material Supported Ionic Liquid Mediated Reusable Hantzsch Reaction

“…On the basis of the above results and the analogous mechanisms discussed in the literatures,, a possible catalytic mechanism for the Hantzsch reaction was proposed in Scheme . Ethyl acetoacetate and aldehyde are firstly activated by Ti‐SBA‐15@IL‐BF 4 by coordination with O atom, then intermediate I was formed by the nucleophilic attack of ammonium acetate and aldehyde on the activated carbonyl of ethyl acetoacetate by enolate formation and adol condensation.…”

“…While the reaction can be traditionally effected with protonic or Lewis acidic catalysts, there have been an urgent need to develop new and efficient catalytic systems to perform this transformation. In this regard plenty of representative catalysts have been developed for Hantzsch reaction, including LiBr, sulfated polyborate, Fe‐TUD‐1, PPA‐SiO 2 , nanoZnO, BiBr 3 , MOFs,, Cu‐NP/C, nano‐γ‐Fe 2 O 3 ,, LTNPs, [Ru(bpy) 3 ] 2+ , and others . However, despite the efficiency of these protocols, most of them still suffer from problems including cumbersome operation and corrosive environment.…”

Sulfated polyborate: A mild, efficient catalyst for synthesis of N-tert-butyl/N-trityl protected amides via Ritter reaction

“…The catalyst was prepared and characterized by various analytical techniques such as potentiometric analysis, Fourier transform infrared spectroscopy (FTIR), X-ray Sulfated polyborate catalyzed N-tert-butyl/N-trityl protected amides 417 diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDAX). 44 Recently, we have reported an efficient sulfated polyborate as a catalyst for one-pot multicomponent synthesis of 3,4-dihydropyrimidin-2(1H )-ones/thiones via Biginelli reaction, 44 synthesis of α-aminophosphinates via Kabachnik-Fields reaction, 45 synthesis of quinoxalines, 46 Hantzsch 1,4-dihydropyridines, 47 and Kindler reaction 48 all under solvent-free conditions. Its ease of preparation, high stability, mild acidity, and reusability prompted us to explore its potential to catalyze other useful reaction transformations.…”

Synthesis of Dihydropyridine Derivatives under Eco‐friendly Approach and Investigation of Cytotoxic Activity

“…In addition, these derivatives were involved in oxidation–reduction reactions and act as an antitumor agent and anti‐inflammatory drugs . There are many synthetic methods that have been reported for the synthesis of dihydropyridine compounds using different catalysts and reagents like ammonium carbonate , tetramethylsilyl iodide , meglumine , grinding conditions , and other methods . Even though a diversity of tactics have been familiar and are establishing to have individual benefits, they experience from each other disadvantages, for example, multistep, toxic reagents, higher temperature conditions, heavy catalysts, and chemical exposure into the environment.…”