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At present, it is an acceptable fact that there is a relationship between the ignition delay time and viscosity of hypergolic energetic ionic liquids (HEILs). With this presumption, an investigation was made to obtain the best logical relationships between ignition delay time, viscosity and molecular structure of hypergolic imidazolium ionic liquids. For this reason, the 3D chemical structure of a collected database of 50 imidazolium ionic liquids was encoded into a total number of 3250 diverse types of molecular descriptors, which are representatives of various physicochemical properties of these ionic liquids. Then, the MLR-ANN approach was applied to obtain the most important molecular descriptors on these relationships. The obtained results of the proposed 3D QSPR models were applied as a criterion for designing new hypergolic imidazolium ionic liquids with the desired ignition delay time and viscosity. Moreover, the predictive ability of the final derived models was evaluated by both internal and external validation methods. The results of this work can assist the computer-aided molecular design researchers to find out or design new HEILs with optimum physicochemical properties.

In this study, a new class of energetic phthalate plasticizers based on imidazolium ionic liquids (ILs) were synthesized. The structure of the synthesized compounds was confirmed by 1HNMR, 13CNMR, and FT-IR. The thermal stability of nitrocellulose (NC)/plasticizer blends was also evaluated by thermogravimetric analysis (TGA). The compatibility of the NC with three synthesized energetic plasticizers was studied by differential scanning calorimetry (DSC), scanning electron microscope (SEM), and density functional theory (DFT) methods. The glass transition temperatures of the NC/synthesized plasticizer blends were determined by DSC and showed desirable lowering of glass transition temperature with a single peak and low temperature, which indicates the compatibility of NC with the synthesized IL plasticizers. The SEM images of plasticized films show smooth surfaces which are resulted from the good compatibility of the plasticizers with NC. The predicted relative trend of interaction energies between NC and plasticizers is well correlated with the corresponding trend of Tg of NC/plasticizer blend. In addition, molecular electrostatic potential (MEP) calculations were performed for all plasticizers/NC. Total electron density for the DEP/NC, 3a/NC, 3b/NC and 3c/NC samples are respectively 0.0388, 0.0942, 0.0944 and 0.0823. There is a very good regression (R2 = 0.9126) between these values and the calculated values of the interactions energy. In this study, a new class of energetic phthalate plasticizers based on imidazolium ionic liquids were synthesized. The compatibility of NC with these energetic plasticizers was studied by differential scanning calorimetry (DSC) and density functional theory (DFT) methods.

Ketamine [2-(2-chlorophenyl)-2-methylamino-cyclohexan-1-one] has been used in both veterinary and human medicine. In this research, a new and efficient protocol has been developed for the synthesis of ketamine, by using hydroxy ketone intermediate. Synthesis of this drug has been done in five steps. At first, the cyclohexanone was made to react with 2-chlorophenyl magnesium bromide reagent followed by dehydration in the presence of an acidic ionic liquid, 1-methyl-3-[2-(dimethyl-4-sulfobutyl-ammonium) ethane] imidazolium hydrogen sulfate to obtain 1-(2-chlorophenyl)-cyclohexene. The oxidation of the synthesized alkene by potassium permanganate gave corresponding hydroxy ketone intermediate. The imination of this intermediate by methyl amine and finally the rearrangement of the obtained imine at elevated temperature resulted in the synthesis of ketamine. All of the intermediates and the product were characterized by 1H-NMR and IR spectroscopies. No need to use toxic bromine (which is used in most of the reported procedures for the synthesis of ketamine), high reaction yields and use of commercially available and safe materials and no need to use corrosive acids in the dehydration step are some of the advantages of this procedure over the common reported ones for the snthesis of ketamine. An efficient five-step protocol for the synthesis of ketamine was developed. Cyclohexanone reacted with 2-chlorophenyl magnesium bromide, followed by dehydration with acidic ionic liquid. Oxidation of the alkene gave corresponding hydroxy ketone intermediate. The imination of this intermediate and rearrangement of the obtained imine finally produced ketamine.

Computer-aided molecular design (CAMD) is a well-known tool for the theoretical assessment of chemical structures before their experimental synthesis. In this study, we used this method to consider the important criteria for a chemical structure as an energetic plasticizer for an energetic azido binder. The number of new azido-ester structures were initially designed, and their physicochemical and energetic properties were determined via theoretical calculation by molecular dynamics simulations and machine learning-based methods. Considering the balances between several criteria, two of these theoretical chemical structures (including GTAA (glyceryl tris(azidoacetate)) and TEGBAA (triethyleneglycol bis(azidoacetate))) were then selected, synthesized, and characterized. The comparison of experimental and theoretical results to evaluate the physicochemical properties of these new azido-ester plasticizers showed an acceptable agreement between the two methods. Finally, the compatibility and efficiency of these two new azido-ester plasticizers on the rheological and thermal properties of glycidyl azide polymer (GAP) were investigated using rheometry and DSC analyses, and compared with some common energetic plasticizers. The results confirmed that these two new azido-esters are appropriate plasticizers for GAP since they exhibited higher safety over comparable plasticizers, in addition to the real performance.

Supported diacidic ionic liquid on magnetic silica nanoparticles (SDAIL@magnetic nanoSiO2) was successfully prepared through a multi-step approach. 2,2- bis ((3- methylimidazolidin-1-yl) methyl) propane- 1,3- diol bromide salt was immobilized onto the surface of magnetic silica nanoparticles via covalent bonding to prepare a novel powerful acidic catalyst. The synthesized catalyst was characterized by FT-IR, SEM, TGA, VSM, N2 adsorption–desorption measurements and acid-base titration. The catalytic activity of the prepared SDAIL@magnetic nanoSiO2 was investigated for the selective diesterification of alcohols by phthalic anhydride to afford corresponding dialkyl plasticizers under solvent-free conditions. The nature of two acidic counter anions as well as the presence of Lewis acidic species (Fe3O4) on the magnetic nanosilica and high surface area of the nanosilica influenced the behavior of the catalyst. Surperisingly, the high acidic character of the catalyst facilitates the reaction with a short reaction time. Furthermore, TG analysis strongly demonstrates that major content of IL is still stable on the support up to 290 °C, so catalyst has a good thermal stability. Under the optimized conditions, the conversion of phthalic anhydride was 100% and diester plasticizers were obtained with excellent yields (80–100%). The SDAIL@magnetic nanoSiO2 catalyst showed a good reusability and could be easily separated from the reaction mixture using an external magnet thanks to its superparamagnetic behavior and reused for several runs without significant activity loss. An important advantage of the SDAIL@magnetic nanoSiO2 was its high-hydrophilicity resulted in excellent selectivity towards the formation of only diesters which are commonly used plasticizers in different industries. Graphical abstract

The hybrid catalyst of (NH 4 ) 2 (MimAm) 40 [Mo 132 O 372 (CH 3 COO) 30 (H 2 O) 72 ] (MimAm = 3-Aminoethyl-1-methylimidazolium) was synthesized by self-assembly strategy. Catalyst was successfully used in the selective oxidation of various sulfides to corresponding sulfoxides and sulfones. All reactions were performed in water as a green solvent by 30% aqueous hydrogen peroxide as a green oxidant under mild reaction conditions. The catalyst showed high conversion and excellent selectivity toward a varied range of substrates and demonstrates excellent chemoselectivity in which other active functional groups such as hydroxyl and C C bond have been tolerated. Also, this hybrid catalyst could be simply separated by filtration, and showed excellent reusability without loss of activity after seven cycles.

Cu0.5Co0.5Fe2O4 magnetic nanoparticles were prepared, characterized and employed as bench-top, highly active and magnetically separable nanocatalysts for the synthesis of 2-amino-4H-chromene derivatives. A wide range of 2-amino-3-cyano-7-hydroxy-4(phenyl)-4H-chromenes were synthesized with high isolated yields during very short reaction times using Cu0.5Co0.5Fe2O4. Interestingly, the catalyst could be separated using only a simple magnetic decantation and reused six times with no considerable loss of efficiency. The high catalytic activity of Cu0.5Co0.5Fe2O4 nanoparticles was attributed to the presence of both copper and cobalt in its framework, which provide a synergistic catalytic effect with enhanced activity in comparison to single metal-incorporated spinels.

Two new functionalized diacidic ionic liquids (FDAILs) including hydroxyl functionalized diacidic ionic liquid (HFDAIL) and sulfonated diacidic ionic liquid (SFDAIL) were synthesized and characterized by 1HNMR, 13CNMR and FT-IR. The catalytic activities of these FDAILs were examined in esterification reaction of anhydrides with some alcohols to give corresponding dialkyl plasticizers under solvent-free conditions. The results indicate that HFDAIL, as hydroxyl-bearing catalyst, show better catalytic performance. Under the optimum conditions, using HFDAIL, the conversion of phthalic anhydride was high and diester plasticizers were obtained with good to excellent yields in the presence of only 10 mol% of ionic liquid. All the produced diesters could be easily recovered due to their immiscibility with the ionic liquid. Recycling experiments suggests that these ionic liquids can be reused several times without remarkable loss in their catalytic activity.

In this study, graphene oxide (GO) was modified with N-methyl-4-pyridinamine in order to synthesize a novel nitrogen-containing graphene-based material for application as heterogeneous catalyst in organic transformations. To prepare this catalyst system, first, chlorine-functionalized graphene (CFG) was synthesized using reaction of GO and thionyl chloride (SOCl2) and then it was reacted with N-methyl-4-pyridinamine. As a result, aminopyridine fragments connected to the graphene surface covalently via a C−N linker and form graphene grafted N-methyl-4-pyridinamine (G-NMPA) catalyst. The G-NMPA material was characterized using some different techniques and used as a heterogeneous catalyst in acetylation of alcohols. Results of catalyst activity evaluation demonstrate that G-NMPA has high activity in acetylation of alcohols. Furthermore, the catalyst system was reusable at least for 8 times without remarkable decreasing in its catalytic activity.

A new class of azide-functionalized monocationic and unsymmetrical dicationic ionic liquids (ILs) with low viscosity and high liquid range was synthesized. All of the synthesized ILs, were characterized by FT-IR, 1HNMR, 13CNMR spectroscopies and elemental analysis. Some thermophysical properties including melting point, density, shear viscosity, decomposition temperature and heat capacity of the unsymmetrical dicationic azide functionalized IL with dicyanamide (DCA) were measured. To find the unique and general features of this dicationic IL, its properties were compared with the ones of the similar monocationic ILs. The results showed that the shear viscosity, density, thermal stability and heat capacity of the unsymmetrical dicationic IL are higher than monocationic analogues. In addition we found that the shear viscosity for the synthesized unsymmetrical dicationic IL containing azide group and DCA anion is 83.9 cP whereas the shear viscosities for other dicationic ILs reported in the literature are higher than 240 cP.

Two highly acidic, imidazolium-based, functionalized dicationic ionic liquids (FDCILs) were synthesized and characterized by FTIR, 1H NMR and 13C NMR. The synthesized FDCILs were used as efficient and green catalysts in the synthesis of phthalate plasticizers through esterification of phthalic anhydride (PhA) with ethanol, n-propanol and n-butanol. Among these two FDCILs, (dimethyl-4-sulfobutyl-ammonium) 1,2-ethan-1-methyl-imidazolium-sulfonic acid hydrogen sulfate performed better. The catalytic activity of FDCIL is related to the density of acidic groups on it and the length of the carbon chain in the cationic part. The influences of the reaction temperature, catalyst dosage, and molar ratio of phthalic anhydride to alcohol on the esterification reaction were investigated. The reusability of the catalyst in these reactions was studied too. The diester phthalates were obtained up to 98.8% yield. The products can be separated easily by decantation from the reaction mixture.

A practical method for the selective epoxidation of alkenes was discovered using HxPMo12O40 ⊂ H4Mo72Fe30(CH3COO)15O254 as a catalyst in the presence of H2O2 as a green oxidant. However, the simple catalyst system involving polyoxometalates and H2O2 exercised the most successful system in obtaining high to excellent yields of epoxide products for different alkenes, including aromatic and aliphatic alkenes at room temperature in water. The effectiveness of this catalyst is evidenced by 99% selectivity to epoxide and 97–99% efficiency of H2O2 utilization. The stability of PMo ⊂ Mo72Fe30 under a catalytic reaction has been confirmed by XRD, FT-IR and Raman spectroscopies.

In this study, meso-tetrakis[4-(methoxycarbonyl)phenyl]porphynatopalladium(II) as a macrocyclic palladium complex was covalently grafted to the surface of graphene oxide (Pd-TMCPP-GO). The Pd-TMCPP-GO was characterized using microscopic and spectroscopic techniques for confirmation of functionalization. The prepared catalyst was checked in a Suzuki reaction. The catalytic system showed high catalytic activity in this reaction and the yields of the products were good to excellent. Also, the proposed catalyst was reusable for seven runs with no significant decrease in catalytic activity.

Two new dicationic ionic liquids (DILs) functionalized with diols on their linkages were synthesized. Elemental analysis, FT-IR, 1H and 13CNMR spectroscopies were applied to identify the molecular structure of these compounds. Some thermophysical properties of these DILs, including density, thermal behavior and heat capacity, were investigated. To find the effect of the hydroxyl groups and H-bonding on the thermophysical properties of these DILs, another DIL with the same anion and linkage chain length but without a hydroxyl functionality was synthesized. Density functional theory (DFT) was used to study the adsorption of the anion on the cation and the strength of H-bonding in 2,2-bis(1-(1-methylimidazolium)methylpropane-1,3-diol dicyanamide). For this purpose, the electronic and structural properties including binding energies (Eb), band gap values (Eg) and partial densities of state (PDOS) were calculated. DFT calculations revealed both strong H-bonding and electrostatic interactions between the hydroxyl groups of the cation and dicyanamide anion in this DIL. Among the more interesting findings for diol functionalized DILs, their thermal stability range generally is higher than DILs without a hydroxyl functionality. The decomposition temperature for 1,3-bis(3-methylimidazolium-1-yl)propane dicyanamide is 465.2 K, whereas 2,2-bis(1-(1-methylimidazolium)methylpropane-1,3-diol dicyanamide) and 2,2-bis(1-(1-vinylimidazolium)methylpropane-1,3-diol dicyanamide) have higher Td values of 524.6 and 525.8 K, respectively. In addition, diol functionalized DILs have higher heat capacities and densities than corresponding DILs without diol functionality.

In this study, a phosphine group was chemically grafted to the surface of graphene in order to prepare a reusable ligand with high surface area, incorporating a phosphine moiety. The treatment of graphene oxide (GO) with hydroxide followed by an aqueous work-up yields an OH-functionalized graphene material (GOH) via ring-opening of the epoxide groups. Reaction of GOH with chlorodiphenylphosphine (ClPPh2) gives a new material, GOPPh2 (PFG), which can be used for stabilization of metal nanoparticles or complexation of transition metals in order to prepare a reusable metal catalyst. Stabilization of palladium nanoparticles on the surface of GOPPh2 resulted in the production of an efficient heterogeneous Pd catalyst (PFG–Pd) for application in C–C and C–N bond formation reactions. The PFG–Pd catalyst was characterized using some different microscopic and spectroscopic techniques such as FT-IR, XRD, TEM, SEM, EDX, and ICP analysis. The applicability of the PFG–Pd catalyst was evaluated in Heck, Suzuki and N-arylation reactions. The catalyst system showed high catalyst activity in these processes and the target products were obtained in high isolated yields. The PFG–Pd catalyst was reusable in these reactions for at least 5 times with no significant decrease in its catalytic activity.

Boron is traditionally used as an additive in energetic systems as a result of the high density of energy. In particular, the existence of the naturally formed boron oxide (B2O3) layer retards the reactivity by acting as a barrier if it cannot be efficiently removed. In this study, the new dicationic ionic liquid based on dicyanamide anoins was synthesized and used as a protective ligand for boron nanoparticles. The effects of newly synthesized ionic liquid are investigated by a combination of X-ray diffraction (XRD), energy-dispersive X-ray (EDX), scanning electron microscopy (SEM), dynamic light scanning (DLS), ζ-potential measurements, X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA). It was found that this ionic liquid binds to boron well enough and protects the boron surfaces from oxidation during air exposure.

In this study, two novel acidic ionic liquids, including a hydroxyl functionalized diacidic ionic liquid [HFDAIL] and a sulfonated diacidic ionic liquid [SFDAIL], were prepared and immobilized on the surface of silica nanoparticles (SNPs) via hydrogen bonding. The materials were characterized by FT-IR, NMR, SEM, nitrogen physisorption measurement, TGA and acid-base titration. The catalytic activity of the prepared catalysts was investigated in the synthesis of phthalate, maleate and succinate diesters under solvent-free conditions. It was found that nanosilica@[HFDAIL] with higher availability of acidic sites and higher hydrophilicity was more efficient compared to the nanosilica@[SFDAIL]. Notably, nanosilica@[HFDAIL] catalyst has also demonstrated excellent selectivity for the diester product while the monoester product was predominant in the case of nanosilica@[SFDAIL] even after prolonged reaction time or higher catalyst loading. In addition, the nanosilica@[HFDAIL] catalyst could be separated by simple filtration and reused several times without any significant loss of catalytic performance, but a remarkable decrease in activity was observed for nanosilica@[SFDAIL] in the next runs. SYNOPSIS Two novel acidic ionic liquids, including a hydroxyl functionalized diacidic ionic liquid [HFDAIL] and a sulfonated diacidic ionic liquid [SFDAIL], were prepared and immobilized on the surface of silica nanoparticles via hydrogen bonding. The catalytic activity of the catalysts was investigated in the synthesis of diesters under solvent-free conditions.

Novel dual dicyanamide-based ionic liquids consisting of coupled ammonium–imidazolium cationic structures were synthesized and their thermal properties were studied. The molecular structures of these compounds were identified by NMR, FT-IR and CHN analysis. Viscosity measurements showed that the new ionic liquid with vinylimidazolium group has lower viscosity than the ionic liquid with methylimidazolium group. However, the densities of the new synthesized compounds are almost same. Thermal behaviors and heat capacities of these ionic liquids were also investigated by thermogravimetry (TGA) and differential scanning calorimetry (DSC). The results suggest that the new ionic liquids have thermal stabilities up to 200 °C, as well as reasonable heat capacities in the range 25 to 100 °C.

This paper introduces a simple model for prediction of one electron reduction potential [E(RNO2/R•NO2–)] of various nitroaryl compounds. The new method uses energy difference between highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) in gas phase at the B3LYP/6-311++G** level (ΔEHOMO-LUMO) and some structural parameters. It was used for 35 nitroaryl compounds including nitrobenzenes, nitrofurans, 2-nitroimidazoles, 4-nitroimidazoles, 5-ninuintidazoles, nitroazaindoles, nitroacridines, and miscellaneous nitroaryl compounds. The root mean square (rms) percent deviation and the average absolute error of predictions of E(RNO2/R•NO2–) relative to experiment were decreased from 12.4 % and 0.42 V to 3.5 % and 0.11 V, respectively, upon consideration of several structural parameters. Increment of the value of ΔEHOMO-LUMO and inclusion of specific polar groups can increase thermodynamic stability of these compounds.

Several new monocationic and unsymmetrical dicationic azide functionalized ionic liquids (ILs) were synthesized. FT-IR, 1H NMR, 13C NMR and elemental analyses were applied to identify the molecular structure of these compounds. The density of these ionic liquids was measured too. Unsymmetrical dicationic ionic liquids had higher density than monocationic analogues. The shear viscosity of a dicationic ionic liquid ((1-(2-azido-3-methyl-3H-imidazole-1-ium) propyl)-3-vinyl-3H-imidazole-1-ium di-dicyanamide) and its corresponding monocationic analogue were also measured. Further thermal behaviour and heat capacity of this dicationic ionic liquid were investigated by TGA and DSC techniques. TGA analysis suggested that the decomposition temperature increases with increasing the heating rate and unsymmetrical dicationic ionic liquid has good thermal stability (up to 502.4–533.6 K) and heat capacity (298–343 K).

Highly regioselective dinitration of toluene with nitric acid as nitrating agent in the presence of Cu1−xCoxFe2O4 (0 ≤ x ≤ 1) as nanocatalysts is described. The results of this protocol show that this nitration system can significantly improve the selectivity and the yield of 2,4-dinitrotoluene. The prepared spinel ferrites were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR). Copper and cobalt synergy (50% : 50%) in spinel ferrite also shows the best catalytic activity in the selectivity of dinitrotoluene under solvent-free conditions.

Sulfonated reduced graphene oxide (RGO-SO3H) was found to be an efficient catalyst for one-pot synthesis of a class of 2-amino-3-cyano-7-hydroxy-4H-chromenes derivatives using multicomponent reaction (MCR) of phenols, aldehydes and malononitrile under mild and green conditions. The reaction was performed in water as a green solvent and range of 2-amino-3-cyano-7-hydroxy-4H-chromenes were obtained in good to excellent yields. The RGO-SO3H was reusable at least 5 times without significant decrease in its catalytic activity.

Copper and cobalt substituted spinel ferrites Cu1-xCoxFe2O4 (0≤X≤1) have been synthesized by using hydrothermal method. The resultant spinel ferrites were systematically characterized by different techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and Fourier transform infrared spectroscopy (FT-IR). It was indicated that all the resultant spinel ferrites obtained by the hydrothermal method had the single-phase crystalline. The resultant spinel ferrites were employed in the synthesis of 14-aryl-14-H-dibenzo[a,j]xanthene derivatives. It was found that the nanocatalyst Cu0.5Co0.5Fe2O4 displays the best performance in the synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes. The catalyst was reused several times without significant loss of its activity for the preparation of desired product. In addition high yields of the products, solvent-free conditions and reusability of the catalyst are other worthwhile advantages of the present study.

The present study describes the synthesis, characterization, and catalytic activity of sulfonated multi-walled carbon nanotubes and sulfonated single-walled carbon nanotubes in the tert-butylation of p-cresol. The catalysts were prepared using a chemical and simple process and it characterized by scanning electron microscopy, Fourier transform infrared, and Raman spectroscopy, thermogravimetric analysis, and acid–base titration. The sulfonated multi-walled carbon nanotubes and sulfonated single-walled carbon nanotubes have been used as practical heterogeneous catalytic systems in the tert-butylation of p-cresol under solvent-free conditions. Sulfonated multi-walled carbon nanotubes with the highest total density of SO3H groups possessed high activity for p-cresol conversion and high selectivity than the sulfonated single-walled carbon nanotubes. This methodology offers some advantages of high selectivity, and high yields, easy work-up, solvent-free conditions, and reusable catalyst. Moreover, the catalytic system was used in scale-up under similar optimized reaction conditions.

Tungstosilicic acid was found to be an efficient catalyst for the synthesis of trisphenols using the reaction of 2,6-bis(hydroxymethyl)phenols with phenols in an aqueous medium. The catalytic reactivity of tungstosilicic acid in boiling water was examined with a series of substrates, demonstrating that this catalyst is reactive in the presence of a variety of functionalities.

A novel series of sulfonic acid-functionalized ionic liquids (SFILs) was found to act as efficient catalysts for ortho-tert-butylation of p-cresol with methyl tert-butyl ether (MTBE) as the tert-butylating agent without an added solvent. The mono o-tert-butylated product was obtained in up to 80.4% isolated yield and 95.2% selectivity under such green conditions. No O-tert-butylated byproducts were formed.

Highly sulfonated single-walled carbon nanotube-catalyzed synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes in excellent yields and very short reaction times. Sulfonated single-walled carbon nanotubes are prepared using a chemical and simple process and it characterized by Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, Thermal gravimetric analysis (TGA) and acid-base titration. The sulfonated single-walled carbon nanotube was easily separated by simple filtration and was recycled eight consecutive times without any loss in its activity.

In this study, a simple and green method has been developed for the synthesis of bisphenolic antioxidants by the reaction of 2-tert-butyl-4-methylphenol and aldehydes in the presence of sulphonated multi-walled carbon nanotubes (MWCNTs–SO3H) as heterogeneous, robust and reusable catalysts under solvent-free conditions. MWCNTs–SO3H was prepared and characterized by some microscopic and spectroscopic techniques including scanning electron microscopy, transmission electron microscopy, FT-IR spectroscopy and Raman spectroscopy. Acidity of the catalyst was measured by acid–base titration. The catalyst was reused several times without efficient loss of its activity for the preparation of bisphenolic antioxidants. In addition, high yields of the products, relatively short reaction times, being solvent-free and non-toxicity of the catalyst are other worthwhile advantages of the present method.

Double mixed Cu0.5Co0.5Fe2O4 ferrite nanoparticles were found as a highly efficient and magnetically separable nanocatalyst for the synthesis of varied flavanone antioxidants. A wide range of flavanone derivatives were prepared with excellent isolated yields within the short reaction times. The catalyst could be separated using a simple magnetic extraction and reused 6 times with no remarkable loss of activity. The high activity of the prepared catalyst was attributed to the cooperative activation of the carbonyl group by both copper and cobalt via a synergistic catalytic effect that facilitates the Micheal addition of the hydroxyl group to the α,β-unsaturated ketone.

The present work focuses on the development of an interpretable quantitative structure-activity relationship (QSAR) model for predicting the anti-HIV activities of 67 thiazolylthiourea derivatives. This set of molecules has been proposed as potent HIV-1 reverse transcriptase inhibitors (RT-INs). The molecules were encoded to a diverse set of molecular descriptors, spanning different physical and chemical properties. Monte Carlo (MC) sampling and multivariate adaptive regression spline (MARS) techniques were used to select the most important descriptors and to predict the activity of the molecules. The most important descriptor was found to be the aspherisity index. The analysis of variance (ANOVA) and interpretable spline equations showed that the geometrical shape of the molecules has considerable effect on their activities. It seems that the linear molecules are more active than symmetric top compounds. The final MARS model derived displayed a good predictive ability judging from the determination coefficient corresponding to the leave multiple out (LMO) cross-validation technique, i.e. r (2 )= 0.828 (M = 12) and r (2 )= 0.813 (M = 20). The results of this work showed that the developed spline model is robust, has a good predictive power, and can then be used as a reliable tool for designing novel HIV-1 RT-INs.

In this work, tertiary butylation of p-cresol was carried out in the presence of Cu1 − xCoxFe2O4 (x = 0 to 1) nanocatalysts by employing methyl-tert-butyl ether (MTBE) and tert-butyl alcohol (TBA) as alkylation agents. Effects of temperature, mole ratio, type and catalyst composition, time and solvent in reaction conditions were investigated. These nanocatalysts were synthesized using hydrothermal method. The characterization of these catalysts was investigated by means of X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FT-IR). These nanocatalysts can be recovered and recycled. A good correlation was found between the activity, in terms of p-cresol conversion and various product selectivities for this reaction, and also the acid–base properties of the catalysts. Nano-sized Cu0.5Co0.5Fe2O4, in comparison to the other nanocatalysts discussed in this report is the most active nanocatalyst. The only product of this reaction is 2-t-butyl p-cresol with selectivity of 100% and p-cresol conversion is 70%. The possible mechanism for this reaction system was discussed based on the reaction results. The reaction mechanism proposed involves the interaction of phenoxide from phenol and the tert-butyl cation from isobutene on Cu1 − xCoxFe2O4.

A very simple and efficient method is described for the protection of alcohols and nucleosides with benzyl monomethoxytrityl and benzyl dimethoxytrityl ethers in the presence of diethylazodicarboxylate and a catalytic amount of ceric triflate. High selectivity was observed for the tritylation of 5′-OH function of nucleosides.

This work presents a new simple method to estimate the melting points of non-aromatic energetic compounds, which contain energetic functional groups C–NO 2 , C–ONO 2 and N–NO 2 . This method can allow the reliable prediction of melting points of non-aromatic energetic materials through a new general correlation. Elemental composition and some specific parameters of non-aromatic energetic compounds are important factors. The predicted results for various non-aromatic energetic compounds show that the present method gives reliable predictions of melting points with respect to previous works. This method has been tested for different newly synthesized explosives with complex molecular structures and energetic compounds with several energetic functional groups.

In the present study, a new collection of 79 functional groups are used to correlate flash point temperature (FP) of pure components. These functional groups construct an accurate neural network−group contribution correlation to estimate flash point of pure components. For developing the model, 1378 pure components of various chemical families are used. Therefore, the model can be utilized to estimate the FP of pure components without any basic limitations.

In this presented work, a quantitative structure‐property relationship study (QSPR) was done for prediction of solubility of C60 fullerene in various solvents. In this study, genetic algorithm‐based multivariate linear regression (GA‐MLR) was applied to obtain most statistically effective molecular descriptors on solubility of C60 in various solvents. All of these molecular descriptors are only calculated from the chemical structure of solvents. For considering nonlinear behavior of appearing molecular descriptors in GA‐MLR section, a feed forward neural network (FFNN) was constructed and optimized for prediction of solubility of C60 fullerene in solvents. Obtained models considerably showed better accuracy in comparison with the previous models.

In this work, a general Quantitative Structure–Property Relationship (QSPR) model (, , and ) for the prediction of flash points of 1030 pure compounds is developed. Genetic Algorithm-based Multivariate Linear Regression (GA-MLR) technique is used to select four chemical structure-based molecular descriptors from a pool containing 1664 molecular descriptors.

Carbon nanofibers were produced from a polyacrylonitrile/N,N-dimethylformamide precursor solution by an electrospinning process and later pyrolysis at temperatures ranging from 500 to 1100°C in an N2 atmosphere for about 1 h. The morphological structure of the nanofibers was studied with scanning electron microscopy. Scanning electron microscopy images of carbonized polyacrylonitrile nanofibers without a gold coating showed that the carbonized polyacrylonitrile nanofibers possessed electrical properties. The thermal behavior of the nanofibers was studied with thermogravimetric analysis. An indirect four-point-probe method was used for the measurement of the conductivity of nanofiber mats. The conductivity increased sharply with the pyrolysis temperature. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007

Copper and cobalt substituted spinel ferrites Cu1-xCoxFe2O4 (0≤X≤1) have been synthesized by using hydrothermal method. The resultant spinel ferrites were systematically characterized by different techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and Fourier transform infrared spectroscopy (FT-IR). It was indicated that all the resultant spinel ferrites obtained by the hydrothermal method had the single-phase crystalline. The resultant spinel ferrites were employed in the synthesis of 14-aryl-14-H-dibenzo[a,j]xanthene derivatives. It was found that the nanocatalyst Cu0.5Co0.5Fe2O4 displays the best performance in the synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes. The catalyst was reused several times without significant loss of its activity for the preparation of desired product. In addition high yields of the products, solvent-free conditions and reusability of the catalyst are other worthwhile advantages of the present study.

The simplest method is introduced for reliable estimating the detonation velocity of large class of CHNO explosives based elemental composition and specific structural groups. There is no need to use heat of formation and the other experimental data for calculation of detonation velocity in the new procedure. Only elemental composition and the number of special structural groups without using heat of formation of explosive is sufficient for reliable desk calculation of detonation velocity. The results show good agreement with experimental values with respect to computed results obtained by complex computer code using BKWS and BKWR equations of state. Predicted velocities of detonation have root-mean-square (rms) percent deviation of 2.2, 5.9 and 5.3 from experimental data for new method, BKWS and BKWR equations of state, respectively.