ORGANIC CHEMISTRY RESEARCH
Year:2023 | Volume:9 | Issue:1|Papers Count:12

The chemistry of nitration reactions is a very powerful tool for the synthesis of pharmaceutical molecules and biological compounds. Carbon-nitrogen (C-N) bond formation is one of the most important reactions in organic synthesis, which plays a key role in the synthesis of biologically active and targeted molecules. Nitro compounds are very useful and have shown their importance in various medical, environmental and military fields for the synthesis of energetic and explosive compounds. Nitration reactions are conducted through various methods and employing diverse reagents, illustrating the multiplicity of their synthesis pathways. Diversifying the chemistry of nitro compounds offers a promising avenue for generating novel targeted molecules, showcasing the potential of these substances and the method itself. The objective herein is to highlight a selection of reagents and pathways for synthesizing nitro compounds that have garnered significant interest from research groups in recent years.

Oliveria decumbens Vent. (Apiaceae family) is an annual herb, and distributes in Syria, Iraq, south-east Anatolia, and Iran. In this study, the effect of acid pre-treatment before hydro-distillation was investigated on the yield and biological properties of the O. decumbens essential oil. Hydro-distillation method was used for the extraction of essential oils from the air-dried powdered flowers (10 g) which were treated with acid solution. Then, the yield as well as antioxidant and insecticidal properties of the essential oils were calculated. The obtained results indicated that the pre-treatment with high acid concentration (0.6 mM HCl) increased the essential oil yield (7.16%) compared to the conventional method (4.4%). Acid solution could hydrolyze the cell walls, and then release secondary metabolites out of the cells. Also, carvacrol and thymol were the major constituents with up to 60% obtained through both methods, and the acid pre-treatment could not change the amount of them, significantly. However, no significant changes were detected in the antioxidant and insecticidal properties of the essential oil, which were pretreated with 0.6 mM HCl, comparing to hydro-distillation method. Therefore, it may be suggested that if high yield is required, the O. decumbens flowers could be treated with acid solution.

Aligned with advancements in synthetic chemistry, this work presents the synthesis and characterization of meglumine sulfate using FT-IR and CHNS analysis. Subsequently, the potential of the synthesized catalyst is explored in the preparation of a class of nitrogen-containing heterocyclic compounds (indenoindolones), which possess significant medicinal and biological properties. The study also reports the optimization of reaction conditions to enable the efficient synthesis and characterization of a broad spectrum of these compounds. Notably, the utilization of meglumine sulfate offers several advantages, including exceptional yields, cost-effectiveness, rapid reaction times, and facile product purification

In this study, we report a successful strategy for the immobilization of cobalt nanoparticles on the surface of the magnetic hydrotalcite Fe3O4/HT-CO. The synthesized nanocatalyst was used in a one-pot and three-component synthesis of 2,4,6-triaryl pyridines from acetophenones, aryl aldehydes, and ammonium acetate under aerobic oxidation. The structural and chemical properties of the prepared nanocatalyst were affirmed by different analyses, including XRD, FE-SEM, EDX, ICP-OES, TGA, FT-IR, and VSM. The aforementioned nanocatalyst could be conveniently removed from the reaction mixture upon applying an external magnetic field. The catalytic activity of the heterogeneous nanocatalyst could be maintained efficiently after recycling up to five successive runs without any noticeable decrease in its catalytic performance or any remarkable changes in catalyst structure. Solvent-free produce, simplicity of the reaction conditions, short reaction times, easy work-up, reusability of catalyst, high yields of the products, as well as the use of a low-cost, eco-friendly catalyst, are advantages of the present protocol for the synthesis of triaryl pyridines.

Due to the importance and many applications of nano-catalysts in various pharmaceutical, petroleum, food industries, etc. they are one of the important applications in new technologies. In this research, Fe₃O₄@THAM-Mercaptopyrimidine magnetic nano-catalyst was used for the synthesis of 2-amino-3-cyanopyridine derivatives in solvent-free conditions at 70℃. Among the advantages of this method are easy separation, an external magnet use, reusability, high stability, compatibility with the environment, and high yield synthesized products, and the structure of the products was identified using melting point and IR, ˡH NMR and 13C NMR spectroscopy.

Progesterone is a steroid hormone mainly associated with female reproductive functions and formulated to treat sexually transmitted diseases and nervous disorders. However, its low water solubility limits its absorption and bioavailability. So, forming inclusion complexes with cyclodextrins is an excellent way to improve its solubility. For this purpose, progesterone was encapsulated in carboxymethyl-β-cyclodextrin (CM-β-CD). UV-Vis, FT-IR, and XRD analyses were performed to characterize the formed inclusion complex.

In this research we investigate heterocyclic compounds (HCs) that play a crucial role in organic chemistry, serving as the foundation for many biological and pharmaceutical molecules. These compounds contain heteroatoms like oxygen, sulfur, and nitrogen within their structure, giving them valuable properties such as antibacterial, antioxidant, and enzyme-inhibiting qualities that are significant in medicine. Dipyrimidines, a type of heterocyclic compound, have a diverse range of applications in medicine including antiviral, antifungal, antibacterial, and anticancer effects. Pyrido[2,3-d:5,6-d′]dipyrimidines, a subgroup of nitrogen-containing heterocyclic compounds, have a unique structure that includes a pyrimidine ring. Despite their usefulness, there are limited methods for synthesizing dipyrimidines, prompting research into various synthesis techniques with different starting materials. The concept of "green chemistry," which promotes environmentally friendly reaction conditions and reduces waste, has gained traction in recent years. Multi-component reactions (MCRs) have emerged as a valuable tool in organic chemistry for efficiently synthesizing complex compounds in a single step. MCRs have advanced the synthesis of natural products and novel chemicals due to their rapid, simple, and versatile nature. These reactions are increasingly popular in academia and industry for producing medicinal compounds.

AbstractUV radiation from the sun is one of the reasons for wood weathering. Wooden structures weathering in addition to waste of these renewable resources entails environmental and economic losses. Therefore, use of nano-additives strengthening the coatings on wooden surfaces against harmful ultraviolet (UV) rays is highly necessary. This work aims to examine the strengthening effect of graphene quantum dots (GQDs) in polyester-wood nanocomposite coating against UV radiation from the sun. To achieve this, graphene quantum dots (0.2wt%) were added to unsaturated polyester (UP) resin, and following the radical polymerization process, UP-GQDs nanocomposite coating was prepared. Afterwards, fluorescence effect and UV-blocking behavior in the pure UP and UP-GQDs coatings were evaluated through photoluminescence and UV-visible spectroscopy methods. Adding GQDs 0.2wt% to the polymer matrix resulted in absorption of ultraviolet rays in all of the UV regions and emission of blue fluorescence. Moreover, by adding GQDs to the UP matrix, pull-off adhesion strength of the nanocomposite was raised compared to the pure coating.

Chlorobenzene is directly used in chemical reactions as a precursor for the manufacture of chemicals, pigments, pesticides or solvents for oil, wax, resin, rubber and is prepared in different ways in liquid phase or gas phase. The gas phase is less common in industry due to its high temperature and low efficiency because it makes the reaction uncontrollable and leads to the formation of other chlorinated products. The choice of a catalyst can not only affect the rate of a chemical reaction, but can also sometimes control the nature of the products. In this research, experimental studies on the liquid phase of benzene chlorination in batch wise process are carried out. The effect of the amount of catalyst with constant mass flow on the efficiency of chlorination products was investigated. It was observed that of the amount of 0.13 mol %, by increasing the amount of the catalyst up to 0.25 mol %, the yield of the product (chlorobenzene) and the percentage of the progress of the reaction it gradually increases and then decrease.

In this research, fluorescein-based chemical sensors were designed and synthesized through the Schiff base reaction to identify Cu2+ and Hg2+ cations. For this purpose, at first SP1 and SP2 sensors were synthesized and their structures were investigated and confirmed by 1HNMR and MS spectroscopy methods. Then, their properties as chemical sensors for some metal cations were investigated by fluorescence emission spectroscopy and ultraviolet-visible spectroscopy (UV-Vis). The obtained results indicated that the SP1 and SP2 acted selectively and also showed a color change for Cu2+ and Hg2+ cations, respectively. The reversibility studies in the presence of EDTA showed that the fluorescence was turned on with the addition of the extra amounts of Cu2+ and Hg2+ cations. Also, the data obtained from Job’s graph and fluorescence titration determined that both sensors form complexes with cations in a ratio of 1:1. Since the structures of both SP1 and SP2 are rigid, the fluorescence turned on with a plausible CHEF mechanism.

A new method for the synthesis of 1-amidoalkyl-2-naphthol derivatives based on the reaction of aldehydes, 2-naphthol, and acetamide/benzamide using NiFe2O4@SiO2 bonded 3-methyl-1-(3-(trimethoxysilylpropyl)-1H-imidazolium hydrogen sulfate (A) in solvent-free conditions has been developed.NiFe2O4@SiO2 bonded 3-methyl-1-(3-(trimethoxysilylpropyl)-1H-imidazolium hydrogen sulfate (A) as a heterogeneous solid supported acid catalyst was prepared and characterized by XRD, FE-SEM, EDX, and FT-IR techniques.

A highly sensitive and selective colorimetric chemosensor for Hg2+ ions was prepared by the use of the well-known isatin chromophore, hydrazine hydrate, and 4-hydroxybenzaldehyde. In EtOH solution, the synthesized adsorbent showed a visual color change from melon yellow to dark orange with a remarkably large red shift (75 nm) in the presence of Hg2+. This color change is due to the formation of a 1:1 metal-ligand complex. In complex, nitrogen atom of hydrazone group and oxygen atom of lactam group were coordinated to Hg2+, while the hydroxyl group on the phenyl ring plays an important role in color change. The detection limit of the synthesized colorimetric chemosensor for mercury ions was 1.8±0.2 μM. The H1 was synthesized as a colorimetric chemosensor based on isatin hydrazone and 4-hydroxy benzaldehyde for monitoring mercury ions. The H1 probe showed a high sensitivity to Hg2+ ions, that interact from its nitrogen and oxygen atoms against mercury cations, with a detection limit of 1.8±0.2 μM. In future research, we intend to modify the structure of isatin hydrazone so that it acts as a logic gate to detect two or more agents, showing different color changes.