ahmad nouri - Academia.edu (original) (raw)

Papers by ahmad nouri

Research paper thumbnail of Nano-Fe3O4/In: a heterogeneous magnetic nanocatalyst for synthesis of tetrazole derivatives under solvent-free conditions

Inorganic and Nano-Metal Chemistry, 2022

Research paper thumbnail of Palladium and silk fibroin-containing magnetic nano-biocomposite: a highly efficient heterogeneous nanocatalyst in Heck coupling reactions

Research on Chemical Intermediates, 2021

Supported metal catalysts, for instance, palladium, are one of the foundations of chemical reacti... more Supported metal catalysts, for instance, palladium, are one of the foundations of chemical reactions, especially in C–C bond formation. The present study reports preparation of a magnetically separable palladium-supported nano-biocomposite with a low cost and easy immobilization technique. Fibroin, a natural biodegradable polymer, was used through an in situ method to cover the Fe3O4 nanoparticles to make a nano-biocomposite followed by anchoring palladium on the fibroin surface. The morphology and the structure of palladium-supported nano-biocomposite Fe3O4@fibroin-Pd were characterized by FT-IR, XRD, TGA, SEM, EDX, and TEM techniques. Consequently, the nanocatalyst activity was evaluated in the Heck coupling reactions. Only a very small amount of the nanocatalyst was employed in the reaction, and it showed excellent catalytic activity; in most cases more than 90% efficiency. The significant advantages of employing this nanocatalyst include high catalytic activity, short reaction times, easy separation of the nanocatalyst with an external magnet and great reusability. The results demonstrated that the used nanocatalysts were very active for four consecutive reaction rounds.

Research paper thumbnail of Tetrazole derivatives synthesis using Fe3O4@fibroin-SO3H as a magnetically separable green solid acid nanocatalyst under solvent-free conditions

Research on Chemical Intermediates, 2020

In the present study, a magnetically separable potent solid acid nanocatalyst with a facile prepa... more In the present study, a magnetically separable potent solid acid nanocatalyst with a facile preparation technique was fabricated via incorporation of fibroin as a natural polymer with Fe 3 O 4 nanoparticles. In fact, the Fe 3 O 4 nanoparticles were thoroughly covered by the fibroin protein, followed by treating with chlorosulfuric acid for surface sulfonation. Next, physicochemical properties were characterized using FT-IR, XRD, TGA, SEM, EDX, and TEM techniques to elucidate the Fe 3 O 4 @fibroin-SO 3 H structure. The analyses proved the core-shell structure and the presence of sulfonyl on the surface. The Fe 3 O 4 @fibroin-SO 3 H showed significant activity in the tetrazole derivatives synthesis reactions under solvent-free and relatively mild conditions. The structure of the products was validated using 1 H-NMR and 13 C-NMR. The prepared catalyst showed good stability and reusability even after easy separation by an external magnet for four consecutive reaction rounds. Considering the crucial importance of sulfuric acid catalysis, we believe that Fe 3 O 4 @fibroin-SO 3 H will find wide applications as a separable, green, and potent solid acid nanocatalyst.

Research paper thumbnail of Nano-Fe3O4/In: a heterogeneous magnetic nanocatalyst for synthesis of tetrazole derivatives under solvent-free conditions

Inorganic and Nano-Metal Chemistry, 2022

Research paper thumbnail of Palladium and silk fibroin-containing magnetic nano-biocomposite: a highly efficient heterogeneous nanocatalyst in Heck coupling reactions

Research on Chemical Intermediates, 2021

Supported metal catalysts, for instance, palladium, are one of the foundations of chemical reacti... more Supported metal catalysts, for instance, palladium, are one of the foundations of chemical reactions, especially in C–C bond formation. The present study reports preparation of a magnetically separable palladium-supported nano-biocomposite with a low cost and easy immobilization technique. Fibroin, a natural biodegradable polymer, was used through an in situ method to cover the Fe3O4 nanoparticles to make a nano-biocomposite followed by anchoring palladium on the fibroin surface. The morphology and the structure of palladium-supported nano-biocomposite Fe3O4@fibroin-Pd were characterized by FT-IR, XRD, TGA, SEM, EDX, and TEM techniques. Consequently, the nanocatalyst activity was evaluated in the Heck coupling reactions. Only a very small amount of the nanocatalyst was employed in the reaction, and it showed excellent catalytic activity; in most cases more than 90% efficiency. The significant advantages of employing this nanocatalyst include high catalytic activity, short reaction times, easy separation of the nanocatalyst with an external magnet and great reusability. The results demonstrated that the used nanocatalysts were very active for four consecutive reaction rounds.

Research paper thumbnail of Tetrazole derivatives synthesis using Fe3O4@fibroin-SO3H as a magnetically separable green solid acid nanocatalyst under solvent-free conditions

Research on Chemical Intermediates, 2020

In the present study, a magnetically separable potent solid acid nanocatalyst with a facile prepa... more In the present study, a magnetically separable potent solid acid nanocatalyst with a facile preparation technique was fabricated via incorporation of fibroin as a natural polymer with Fe 3 O 4 nanoparticles. In fact, the Fe 3 O 4 nanoparticles were thoroughly covered by the fibroin protein, followed by treating with chlorosulfuric acid for surface sulfonation. Next, physicochemical properties were characterized using FT-IR, XRD, TGA, SEM, EDX, and TEM techniques to elucidate the Fe 3 O 4 @fibroin-SO 3 H structure. The analyses proved the core-shell structure and the presence of sulfonyl on the surface. The Fe 3 O 4 @fibroin-SO 3 H showed significant activity in the tetrazole derivatives synthesis reactions under solvent-free and relatively mild conditions. The structure of the products was validated using 1 H-NMR and 13 C-NMR. The prepared catalyst showed good stability and reusability even after easy separation by an external magnet for four consecutive reaction rounds. Considering the crucial importance of sulfuric acid catalysis, we believe that Fe 3 O 4 @fibroin-SO 3 H will find wide applications as a separable, green, and potent solid acid nanocatalyst.