Tetrazoles, characterized by a five-membered ring containing four nitrogen atoms, exhibit diverse chemical properties and have found applications in pharmaceuticals, agrochemicals, and materials science. Traditional methods of tetrazole synthesis often involve lengthy procedures, harsh conditions, and environmental hazards. The emergence of nano-catalysts has addressed these challenges, offering efficient, selective, and environmentally friendly routes for tetrazole synthesis.
Fig. 1 Tetrazole derivatives possess devised important pharmacological properties (Swami S.; et al. 2021).
Related Products
Nanocatalysts for Tetrazole Synthesis
Various types of nanocatalysts have been explored for the synthesis of tetrazoles, each offering unique advantages in terms of catalytic activity, selectivity, and recyclability. Magnetic nanocatalysts, such as Fe3O4-based nanoparticles functionalized with organic ligands or metal complexes, have gained significant attention due to their ease of separation and recyclability. For example, Fe3O4@tryptophan@Ni and Fe3O4@SiO2-APTES-TFA nanocatalysts have demonstrated excellent catalytic performance in the synthesis of 5-substituted tetrazoles.
Similarly, other nanomaterials, including silica-based nanoparticles, metal-organic frameworks (MOFs), and carbon nanotubes, have been functionalized and utilized as efficient catalysts for tetrazole synthesis. For instance, Cu(II)-immobilized MOFs and chlorosulfonic acid-functionalized carbon nanotubes on Fe3O4 nanoparticles have shown remarkable catalytic activity in the formation of tetrazole derivatives.
Boehmite Based Nano-Catalyzed Synthesis of 5-Substitute Tetrazoles
Boehmite, a γ-AlOOH compound rich in surface hydroxyl groups, exhibits enhanced catalytic activity due to its hydrophilic nature. When downsized to the nanoscale, boehmite demonstrates increased reactivity, stability, and surface area, making it an ideal catalyst for organic transformations. Nanostructures like Pd-SMTU@boehmite, boehmite@SiO2@Tris-Cu(I), and BNPs@Cur-Ni have shown remarkable efficacy in synthesizing 5-substituted tetrazoles. These nano-catalysts, characterized by FT-IR, XRD, and SEM, offer high yields, short reaction times, and recyclability. Additionally, functionalized nanostructures, such as Ni-SMTU@boehmite and Schiff base-modified boehmite, further enhance catalytic performance. Palladium-arginine complex immobilized on boehmite nanoparticles (Pd-Arg@boehmite) represents a green catalyst with exceptional substrate compatibility and reusability, making boehmite-based catalytic systems promising candidates for green synthesis routes.
Magnetic Nano-Catalyzed Synthesis of Tetrazoles
Magnetic nanoparticles have emerged as versatile catalysts due to their ease of preparation, high efficiency, and recyclability. For instance, Fe3O4@chitin and Fe3O4@tryptophan–La were utilized for synthesizing 5-substituted-1H-tetrazoles, offering high yields and short reaction times. Additionally, Fe3O4-adenine-Zn and Fe3O4@fibroin-SO3H facilitated the synthesis of tetrazoles under solvent-free conditions with excellent yields. Fe3O4@CNT-SO3H nano-catalyst exhibited efficient performance in multicomponent reactions, delivering high product yields and eliminating the need for toxic solvents. Moreover, Fe3O4-based catalysts like Fe3O4@BNPs-CPTMS-chitosan-Pd(0) and unmodified nano Fe3O4 demonstrated remarkable catalytic activity for 5-substituted tetrazole synthesis, promising green and sustainable synthetic routes with enhanced yields and easy recyclability.
Copper-Based Nanomaterial Catalyzed Synthesis of Tetrazoles
Recent years have seen significant attention directed towards the development of copper-based nanomaterials, particularly in the realm of nano-catalysis for organic transformations. These materials offer versatility in oxidation states, facilitating reactivity through various pathways. Apart from catalysis, they find applications in nanotechnology, electrocatalysis, and photocatalysis. Notably, Cu-immobilized heterogeneous nano-catalysts have been extensively employed in synthesizing tetrazole derivatives. For instance, various Cu-based catalysts like Cu(II)/Fe3O4@APTMS-DFX, Cu-MOF-1, Cu-MOF-2, CuO/aluminosilicate, and biochar-supported Cu-TBA have shown promising results, offering advantages such as recyclability and high yields. Solid supports like SBA-15 and Fe3O4@SiO2 have been utilized for anchoring Cu species, enhancing catalytic efficiency. Additionally, novel catalysts like Fe3O4/SiO2/CPTMS/MT/Cu and Fe3O4/SiO2/CPTMS/AT/Cu, incorporating amino acids, have demonstrated efficient synthesis of tetrazoles. These developments represent strides towards sustainable and efficient nano-catalysis, addressing the demand for environmentally friendly catalytic systems.
Zinc Oxide Derived Nanomaterials Catalyzed Synthesis of Tetrazoles
Zinc oxide (ZnO) nanoparticles, renowned for their Lewis acidic surface sites and exceptional physical properties, serve as efficient heterogeneous acid catalysts. With wide bandgap energy and high surface area, ZnO finds applications in diverse fields like catalysis, photodegradation, and electronics. Nanocrystalline ZnO catalyzes the synthesis of 5-substituted-1H-tetrazoles via [3+2] cycloaddition, yielding high product yields (69–82%) at 120–130 °C with excellent recyclability. Mixing ZnO with metal oxides like Co3O4 enhances its acidity, boosting catalytic activity for tetrazole synthesis. Moreover, silver-doped ZnO nanorods facilitate photo-triggered synthesis of 1,5-disubstituted tetrazoles, offering high yields (97%) under optimized conditions. Additionally, ultrasound-assisted synthesis using ZnO nanoparticles demonstrates efficient tetrazole formation (88–96% yield) with mild reaction conditions and excellent catalyst recyclability, emphasizing cost-effectiveness and eco-friendliness.
Carbon-Based Nanomaterials Catalyzed Synthesis of Tetrazoles
Carbon-based nanomaterials, including carbon nanotubes, graphene, and graphene oxide, serve as versatile catalyst supports for various organic transformations due to their exceptional properties like high stability, large surface area, and easy functionalization. For instance, a multi-walled carbon nanotube supported AMWCNTs-O-Cu(II)-PhTPY nano-catalyst efficiently synthesizes 1-substituted and 5-substituted-1H-tetrazoles, offering high yields and recyclability. Similarly, a graphene oxide-supported GO/Fe3O4@PAA-Cu-complex nano-catalyst facilitates one-pot synthesis of tetrazoles with excellent recyclability over six cycles. Additionally, a Cu/AC/r-GO nanohybrid nano-catalyst on graphene oxide supports the synthesis of 5-substituted-1H-tetrazoles, demonstrating high stability and recyclability, enhancing the efficiency of the catalytic process. These carbon-based nanostructures represent promising catalyst platforms for diverse organic transformations, providing environmentally benign and cost-effective solutions.
Composite Nanomaterial Catalyzed Synthesis of Tetrazoles
Composite nanomaterials, combining two or more different constituent materials, exhibit enhanced physical and chemical properties. For instance, a biosynthesized Pd/MnO2 nanocomposite catalyst efficiently synthesizes 5-aryl-1H-tetrazoles, offering high yields and simple preparation. A magnetic Fe3O4@MCM-41-SB-Cu nanocomposite catalyzes 5-substituted-1H-tetrazoles synthesis with excellent recyclability. Similarly, a Fe3O4@SiO2/aza-crown ether-Cu(II) nanocomposite facilitates synthesis of 1,2,3-triazoles and tetrazoles with admirable yields and reusability. Cu NPs@Fe3O4-chitosan nano-catalyst displays high catalytic activity for various tetrazole formations, with advantages including easy work-up and high yields. Biosynthesized Ag/sodium borosilicate nanocomposite and RuO2/MMT nanocomposite are also effective catalysts for tetrazole synthesis, offering high yields, short reaction times, and recyclability. These composite nanomaterials represent promising catalysts for diverse organic transformations, providing efficient and sustainable solutions.
Miscellaneous Nano-Catalyst for the Synthesis of Tetrazole
Various research groups have explored miscellaneous nano-catalysts for the synthesis of tetrazole, in addition to the broad range of nanostructured catalysts available. For instance, Movaheditabar and Javaherian investigated the use of nano-silica melamine trisulfonic acid as a heterogeneous catalyst for producing 5-substituted-1H-tetrazoles. They found that the activity of nitriles plays a crucial role in the [3+2] cycloaddition reactions with sodium azide, with aliphatic nitriles yielding better results in a shorter time compared to aromatic nitriles. Additionally, nickel zirconium phosphate and β-Ni(OH)2 nanoparticles have also been identified as efficient catalysts for tetrazole synthesis, offering advantages such as high yields and short reaction times. The development of TiCl4·SiO2 and magnetic Fe3O4@SiO2@CPTMS@AMTDA@Co heterogeneous catalysts further demonstrates the versatility of nano-catalysts in industrial-scale applications, with the ability to recover and reuse the catalyst without significant loss in catalytic activity.
Conclusion
Nanocatalysts have emerged as powerful tools for the synthesis of tetrazoles, offering unprecedented efficiency, selectivity, and sustainability. The integration of nanotechnology with catalysis has revolutionized traditional synthetic approaches, paving the way for the development of novel tetrazole derivatives with diverse applications. As research in this field continues to advance, nanocatalysts are poised to play a central role in driving innovation and addressing challenges in tetrazole synthesis and beyond.
References
- Swami S., et al. Nanomaterial catalyzed green synthesis of tetrazoles and its derivatives: a review on recent advancements. RSC Aadvances. 2021, 11 (62): 39058-86.
- Kazemi M. Copper catalysts immobilized on magnetic nanoparticles: catalysis in synthesis of tetrazoles. Nanomaterials Chemistry. 2023, 1 (1): 1-1.
.
