نشریه پژوهش های شیمی
سال دوم شماره 2 (پیاپی 3، پاییز و زمستان 1398)

In this research, a highly efficient new method for the synthesis of N,N′-alkylidene bisamides has been introduced. The reaction between aromatic aldehydes and primary amides in the presence of acidic ionic liquid 1,3-disulfonic acid imidazolium chloride ([Dsim]Cl) under solvent-free conditions afforded these compound in high yields and in short times. Amide functional group is of importance in chemical and medicinal industries. For example, bisamides have been extensively applied in the synthesis of peptide- and pseudo-peptide-containing biological materials, and other medicinal compounds. The best method for the preparation of N,N′-alkylidene bisamide is the condensation reaction between amide and aldehyde; several catalysts have been reported for this reaction. However, the previous methods for the synthesis of these amide derivatives have drawbacks, as following: high reaction temperature, moderate yields, long reaction times, difficult procedure for catalyst preparation, the use of toxic and volatile organic solvents as reaction media, and no agreement with green chemistry protocols. Thus, introducing new catalysts for this reaction, which have not these drawbacks, is of importance.

Some new dioxaphosphorinane derivatives were synthesized with general formula RC(O)NHP(O)OCH2C(CH3)2CH2O [R = 4-CH3OC6H4 (1), 4-NO2C6H4 (2), C6H5 (3), 4-CH3OC6H4NH (4)]. The structures of the compounds were established by IR, 1H NMR, 13C, 31P NMR spectroscopy. Two separate signals for CH3 groups on dioxaphosphorinane rings and the Hequatorial and Haxial atoms of CH2 groups in these compounds demonstrate that the synthesized compounds are toward one chair conformation. Besides, all newly synthesized compounds and cyclophosphamide (standard drug, CP) were screened for their anticancer activity against three human cell lines, breast cancer (MCF-7), prostate cancer (PC-3) and cervical cancer (HeLa). Results indicated that compound 4 with phosphinourea backbone and methoxy substitute was found to be the most active with IC50 of 0.03±0.007, 0.011±0.003, and 0.05±0.009 (nM) against MCF-7, PC‐3, and HeLa cell lines, respectively. Further, the structure-activity relationship (SAR) indicates that high lipophilic nature and the molecular volume of 4 have the direct order with its activity.

Research in the field of explosives detection due to the increased use of these materials in terrorist attacks is growing. In this paper, a chemiresistor gas sensor based on Graphene oxide functionalized with 2,2,3,3,4,4,5,5-Octafluoro-1,6-hexanediol is provided and its response to 2,4-Dinitrotoluene is studied. response of the sensor by adding the second coating layer on the functionalized graphene oxide show considerable increase the sensitivity and selectivity of the sensor .Linear response range for DNT, 91.8-918 ppb with a detection limit 76 ppb is obtained. Also the RSD to evaluate the repeatability of sensor for 3 replicate measurements was 6.09%.

The removal of toxic pollutions from aqueous waste is nowadays considered as a hot issue being investigated. ]In this research, tetracycline (TC) as an important antibiotic, and malathion (MA) as a toxic organophosphate pesticide are considered for the photodegradation by a high-performance nanocomposite. Co3O4 nanoparticle anchored on graphene oxide based on UiO-66 metal- organic framework were synthesized and tested for photodegradation of tetracycline and malathion. Results showed that the presence of graphene oxide and UiO-66 improves the photodegradation efficiency up to 93% and 81% for tetracycline and malathion, respectively. Furthermore, total organic carbon studies verified the decontamination of this pollutants. Presence of graphene oxide and UiO-66 with high specific surface area, great conductivity, and various functional groups make it as good support for Co3O4 nanoparticles. All experiments show that this nanocomposite can be appointed as a good photocatalyst in the visible light area and it can be an excellent replacement for other photocatalysts.

Ion exchange resins are one of the good tools with great potential to remove metal ions from water sources. The adsorption of chromium ion was investigated by modified poly (styrene-co-maleic anhydride) with 2-aminopyridine and crosslinked with 1, 2 - diamino ethane (CSMA-AP) under ultrasonic irradiation as an ion exchange resin in aqueous solutions. In this work, crosslinked resin has been synthesized by poly (styrene-co-maleic anhydride) and 1, 2 - diamino ethane. This type of ion exchange resins adsorbs metal ions due to the combination of ionic and coordination intractions, instead of simple electrostatic interactions in conventional anionic or cationic exchange. therefore, the chelating resins, exhibit better selectivity compared to conventional resins. The adsorption behavior of these metal ions on the resin was studied by varying the parameters such as pH (2-7), adsorbent dose (0.5-5 g/L), contact time (0- 180 min) and metal ions concentration (1-40 mg/L). By increasing the initial concentration of chromium ion to about 10 mg / L, Adsorption percentage after increasing was fixed and then decreased. The SEM device was also used to confirm the adsorption process. The MAP technique shows the presence of elements in the nano-sorbent structure, which, as a result of these images, qualitatively adsorption process is well verified. The results showed that the best fit was achieved with the Langmuir isotherm equations. By using these isotherms, maximum adsorption capacities of 20.619 mg/L were obtained, which indicates the high capability of these ion exchange resins for the process of adsorbing and removing chromium ion.

First, in this study, the distilled water was magnetized by a magnetic-cyclic reactor and the properties of the prepared magnetic water. Next, the physical properties of the magnetized water were analyzed and then compared with distilled water. the Physical properties of magnetized and non-magnetized water such as pH changes, oxygen solubility, viscosity, absorption of infrared and ultraviolet radiation, refractive index and solubility were studied. After examining these items, the magnetized water employed in the electrochemical cell as part of the reaction environment to evaluate its effect on the redox behavior of some aromatic compounds, such as the chloroselenobenzene and the 2-hydroxyphenyl which called “Catechol”. The results showed that the magnetized water can change the oxidation and reduction conditions of some aromatic compounds. Based on the obtained results of the designed experiments, we found that there is a relation between magnetization and redox behavior of some compounds and therefore a mechanism for water magnetization as well as the oxidation and reduction behavior of the compounds was presented.

In this project, by using density functional theory the adsorption of 5- Fluorouracil drug on the surface of pristine and B and P doped of Aluminum nitride nano cage (Al12N12) is investigated at different states. According to optimized structures, the quantum and thermodynamic parameters, molecular electrostatic potential (MEP), natural bonding orbitals (NBO) and quantum theory of atom in molecule (QTAIM) for all considered models are calculated. The results of quantum parameter reveal that the gap energy of 5- Fluorouracil drug and aluminum nitride nano cage complex decrease significantly from original state and so the conductivity, reactivity, and optical properties of system increase. These properties confirm that the doped aluminum nitride nano cage is a good candidate to making sensor for 5- Fluorouracil drug. Comparison results of thermodynamic and adsorption energy show that the adsorption energy of 5- Fluorouracil on the surface nano cage is negative and the adsorption process is exothermic and favorable. The AIM and NBO results display that the adsorption of 5- Fluorouracil drug on the surface of nano cage is electrostatic and this property is favorable for using drug delivery in biological system. On the other, hand the calculated results indicate that the B&P doped aluminum nitride nano cage can be a good candidate to making a delivery and sensor for 5- Fluorouracil drug.

Ionic liquids which are known as green solvents have specific physical and chemical properties and include great potential applications in various industries. In other hand, carbon nanotubes due to their outstanding mechanical, thermal and electronic properties have been extensively studied during the last two decades. It has been indicated that the systems containing ionic liquids and other components such as nanostructures and carbon nanotubes have properties which have reduplicated the importance of ionic liquids and carbon nanotubes. In the present paper, recent investigations on the systems containing various ionic liquids and carbon nanotubes by molecular dynamics simulation is reviewed and simulation details and computational methods for performing molecular dynamics simulation of some systems are presented. Using molecular dynamics simulation, it can be demonstrated how ionic liquids disperse the carbon nanotubes. Also, molecular dynamics simulation can be used for investigating the structural and dynamical behaviors of confined ionic liquids inside the carbon nanotubes.

Phosphine (PH3) is a toxic and harmful gas released by the reaction of aluminum phosphide or rice pill in the presence of water, water vapor or stomach acid. Poisoning caused by phosphine is more suicidal and two thirds of the poisoned ones die. In this paper, the structural and electronic properties of (10,0) carbon nanotube and SiC nanotube have been investigated through density functional theory. The PH3 molecule was first placed at the distance about the sum of atomic radius of C/Si of nanotube and P/H of phosphine molecule, inside and outside the nanotube from both H and P atom sides. Then the structure was completely relaxed the electronic calculations were performed on relaxed structures. The results show that SWCNT can weakly adsorb PH3 molecule. However, SiC nanotube has lower adsorption energy toward phosphine and its electronic properties change more after adsorbing PH3 inside or outside the silicon carbide nanotube. Therefore this nanotube is potentially a good candidate for detecting and adsorbing PH3 molecules. Partial densities of state calculations were also performed to find the origin of each adsorption.

In this research synthesis of two new Macrocyclic Cd(II) is reported. For the synthesis of mentioned complexes first, it should be prepared intended aminse and aldehyde. For this mean, the attended amines and aldehyde were prepared according to literature. It should be noted that the amines are known as asymmetric and total asymmetric pendant arm amines. After preparation these appropriate amines and aldehyde, the Macrocyclic complexes were synthesized. This is interesting that the reaction of amine and aldehyde is as [2+2], in addition the prepared complexes of Cd(II) are dinuclear that both Cd(II) centers are bridged with nitrate ion. According to mass spectroscopy the proton transfer has been happen here, finally, the related ligand has been coordinated as N3O donor set, an imine nitrogen, a tertiary nitrogen, a pyridine nitrogen and an oxygen of hydroxyl group. It should be noted that the nitrogen of pyridine group has been coordinated as pendant arm. After preparation and purification the purposed complexes, they were studied by different spectroscopy methods such as IR, NMR and Mass.

Boric acid aqueous solution system as an efficient catalytic system was applied for the reaction of phenyl hydrazine, ethyl acetoacetate and aryl aldehydes to prepare bis(pyrazolyl)methanes. By the reaction of Boric acid with water, H+ was generated and catalyzed the reaction under green and mild condition. In this paper, the synthesis of bis(pyrazolyl)methanes including 4,4´-(arylmethylene)-bis(3-methyl-1-phenyl-1H-pyrazol-5-ol)s was reported by tandem Knoevenagel–Michael reaction of phenyl hydrazine, ethyl acetoacetate and aryl aldehydes in the presence of boric acid aqueous solution system, at 70 °C with high yields and short reaction times. Boric acid aqueous solution system as an efficient catalytic system was applied for the reaction of phenyl hydrazine, ethyl acetoacetate and aryl aldehydes to prepare bis(pyrazolyl)methanes. By the reaction of Boric acid with water, H+ was generated and catalyzed the reaction under green and mild condition. In this paper, the synthesis of bis(pyrazolyl)methanes including 4,4´-(arylmethylene)-bis(3-methyl-1-phenyl-1H-pyrazol-5-ol)s was reported by tandem Knoevenagel–Michael reaction of phenyl hydrazine, ethyl acetoacetate and aryl aldehydes in the presence of boric acid aqueous solution system, at 70 °C with high yields and short reaction times.

So far, various methods have been proposed for the synthesis of hydroxyapatite nanoparticles as the main ingredient in bone and enamel. In each of these methods, by varying initial conditions of synthesis, samples of size and shape, and the ratio of length to diameter can be achieved. In this study, pure hydroxypropyl nanoparticles were prepared using calcium nitrate precursors (Ca (NO3) 2-4H2O) and diammonium hydrogen phosphate ((NH4) 2HPO4) by hydrothermal method. The purpose of this study was to investigate the effects of changes in reaction conditions and the synthesis of this material on the size and shape of the particles. X-ray diffraction (XRD) and scanning electron microscopy (SEM) nanoparticles were investigated. The results of the experiment indicate that the concentration of the raw materials, the method and temperature of calcining, the speed of the addition of materials, the use or non-use of surfactants can have different effects on the size and shape of the hydroxyapatite particles.

In this paper, we have used a simple equation of state to predict the volumetric and thermodynamic properties of liquid refrigerants. The thermodynamic properties such as density ρ, isobaric expansion coefficient α, and isothermal compressibility κ, for some refrigerants e.g. R236ea, R245ca, and R245fa, based on GMA EOS have been calculated and a wide comparison with experimental data was made. This article is devoted to the theoretical study of some thermodynamic properties of the liquid refrigerants over the temperature range between 240K and 440K and pressures up to 580 atm to indicate that the GMA EoS has an acceptable performance for property predictions of pure liquid refrigerants. Our calculated results on the density, isobaric expansion coefficient and isothermal compressibility for the liquid refrigerants are in good agreement with the experimental data. The accuracy of the equation of state is determined by a statistical parameter; Absolute Average Deviation ( AAD). The AAD values show that the GMA equation of state can predict the thermodynamic properties of the refrigerants in the range of temperature and pressure with high precision.