Succinimidinium hydrogensulfate ([H-Suc]HSO4) as a new, green and efficient ionic liquid catalyst for the synthesis of tetrahydrobenzimidazo[2,1-b]quinazolin-1(2H)-one, 1-(benzothiazolylamino)phenylmethyl-2-naphthol, 1, 8-dioxo-octahydroxanthene and bis(indolyl)methane derivatives

An efficient catalysis for the synthesis of pyrimido[1,2-a]benzimidazoles and 1-(benzothiazolylamino)methyl-2-naphthols using ZnO@SO3H@Tropine

In this research and in the line of our researches on the use of nano-substrates modified with ionic liquid in organic reactions, an efficient and green method for the one-pot three-component synthesis of pyrimido[1,2-a]benzimidazole and 1-(benzothiazolylamino)methyl-2-naphthol derivatives is reported using a new nanoporous catalyst formulated as ZnO@SO3H@Tropine. Further analysis of the catalyst for its characterization has been performed using thermal gravimetric analysis (TGA), field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), energy dispersive spectrometer (EDS) and Fourier-transform infrared spectroscopy (FT-IR). The present approach creates a variety of biologically active heterocyclic compounds with excellent yields and short reaction times. Among the other advantages of the current method are: ease of operation, clean reaction profiles and ease of separation. Also, this catalyst can be reused five times without loss of its catalytic activity.

Tungsten oxides: green and sustainable heterogeneous nanocatalysts for the synthesis of bioactive heterocyclic compounds

Tungsten oxide (WO₃) as an efficient heterogeneous catalyst was prepared via a simple hydrothermal route for the synthesis of a wide range of bioactive heterocyclic compounds. The present investigation deals with the rapid and low-cost synthesis of C-3-alkylated 4-hydroxycoumarin, chromene, and xanthene derivatives. WO₃ nanorods (NRs) are successfully envisaged to catalyze desired transformations, demonstrating the wide range of their potential applications in catalysis. Synthetic transformation details, smallest catalytic amounts, excellent product yields, and plausible reaction mechanisms for the formation of these heterocyclic scaffolds are elicidated. As-prepared WO₃ NRs are characterized to confirm their structural, chemical, and morphological parameters by X-ray diffraction, X-ray photoelectron spectroscopy, and field emission scanning electron microscopy measurements, respectively. We discuss the factors that govern the formation of products, and the active role of WO₃ NRs, which are essential for the activation of substrates in the present study of thermal conditions. Herein, detailed synthesis and spectroscopic information of the prepared compounds are reported.

Preparation, characterization, and use of novel Cu@Fe3O4 MNPs in the synthesis of tetrahydrobenzimidazo[2,1-b]quinazolin-1(2H)-ones and 2H-indazolo[2,1-b]phthalazine-triones under solvent-free conditions

Cu@Fe₃O₄ MNPs as novel nanomagnetic reagents were prepared to investigate their catalytic behavior in the preparation of tetrahydrobenzimidazo[2,1-b]quinazolin-1(2H)-ones, as important biologically active compounds. Then, characterization of the synthesized nanoparticles was performed using different methods including Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) analysis, thermogravimetric analysis (TGA), vibrating sample magnetometer (VSM), energy dispersive X-ray (EDX), and scanning electron microscopy (SEM). All reactions were performed with small amounts of the Cu@Fe₃O₄ MNPs under solvent-free conditions. After completion of the reaction, because of the magnetic nature of the nanocatalyst, they could be simply separated with an external magnet and easily reused with no considerable decrease in the catalytic behavior even after seven runs.

Contemporary progress in the synthesis and reactions of 2-aminobenzothiazole: a review

Various protocols for the synthesis and reactions of 2-aminobenzothiazole.

Introduction of Fe3O4@SiO2–ZrCl2-MNPs for the efficient promotion of some multi-component reactions under solvent-free conditions

In the work, the preparation, characterization and use of Fe₃O₄@SiO₂–ZrCl₂-MNPs as nano magnetic reagents in the promotion of some multi-component reactions is reported.