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Funding information Islamic Azad University-Arak BranchAn efficient method for the N-alkylation of poorly nucleophilic amines using ferric perchlorate immobilized on SiO 2 as a catalyst is described. Fe(ClO 4 ) 3 was prepared from mixing iron(III) hydroxide and perchloric acid and adsorbed on silica gel. The catalyst was characterized using various techniques. The supported ferric perchlorate (Fe(ClO 4 ) 3 /SiO 2 ) revealed high efficiency and selectivity for N-alkylation of aromatic amines with alcohols to provide alkylated amines. Various secondary amines were synthesized from primary amines and alcohols in good to excellent yields, with water as the only by-product. The optimization of the reaction conditions was investigated using the response surface method, and involving the Box-Behnken design matrix. The conditions for optimal reaction yield and time were: amount of catalyst = 0.34 mmol, temperature = 60°C and molar ratio of amine to alcohol = 1.2.The catalyst was recovered and reused for five cycles without a considerable decrease in catalytic activity. The stability of the recycled catalyst was investigated. The proposed method has numerous advantages including procedure simplicity, short reaction times, low cost, good to excellent yields, reusability of the catalyst and mild and environmentally benign conditions.

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In this work, phosphomolybdic acid immobilized on chitosan/Fe3O4 as a green catalyst was used for the Hofmann Nalkylation of aniline derivatives with alcohols. H3PMo12O40/chitosan/Fe3O4 (PMo/Chit/Fe3O4) was prepared from the phosphomolybdic acid, chitosan, and Fe3O4 MNPs. Several secondary amines were synthesized from primary arylamines with electron-donating, electron-withdrawing groups, and alcohols in good to excellent yields. The catalyst could be separated using an external magnet and recovered without reducing its catalytic activity. The optimization of the reaction conditions was evaluated using the response surface method (RSM), involving the Box-Behnken design matrix. The simple procedure, only one byproduct (i.e., water), good to excellent yields, easy separation of the catalyst, short reaction times, and environmentally benign conditions were some advantages of this method.

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Background: The benzimidazoles and benzothiazoles have shown relatively high pharmaceutical and biological activities. In recent years, numerous methods have been developed for synthesis of benzimidazole and benzothiazole derivatives using different catalysts. However, only some of the reported procedures are quite satisfactory and most of them have drawbacks. Herein, we report a convenient method for synthesis of benzimidazole and benzothiazole derivatives using a nickel (II) metal-organic framework (Ni- MOF) as a novel and reusable catalyst. The presence of unsaturated metal centers makes metal-organic frameworks to be used as Lewis acid catalysts. Objective: The primary objective of this study was to describe an efficient method for synthesis of benzimidazole and benzothiazole derivatives. Methods: Ni-MOF was prepared using the modified evaporation method and was characterized by FE-SEM, FT-IR, TGA, and XRD techniques.The catalyst was then used to test the synthesis of some benzimidazole and benzothiazole derivatives. The benzimidazoles and benzothiazoles were characterized by Elemental analyses, HNMR and IR techniques. Results: A variety of aromatic aldehydes bearing electron donating groups or electron-withdrawing were reacted with 1,2-phenylenediamine or 2-aminothiophenol using Ni-MOF in good to excellent yields. Conclusion: In summary, a new and highly efficient method was developed and reported for the synthesis of benzimidazole and benzothiazole derivatives using nickel(II) metal-organic framework. The advantages are short reaction times, good to excellent yields, the environmentally benign and simple procedure, stability, nontoxicity, recyclability, and easy separation of the catalyst.

Imidazole derivatives are the foundation of different types of drugs with a wide range of biological activities. In this study, the genetic algorithm–multiple linear regression (GA–MLR), and backpropagation–artificial neural network (BP–ANN) were applied to design QSPR models to predict the quantum chemical properties like the entropy (S) and enthalpy of formation (∆Hf) of imidazole derivatives. In order to draw molecular structure of 84 derivative compounds Gauss View 05 program was used. These structures were optimized at DFT‐B3LYP/6‐311G* level with Gaussian09W. The Dragon software was used to calculate a set of different molecular descriptors, and the genetic algorithm procedure and backward stepwise regression were applied for the selection of descriptors. The resulting quantitative GA–MLR model of ∆Hf, showed that there is good linear correlation between the selected descriptors and ∆Hf of compounds. Also the results show that the BP–ANN model appeared to be superior to GA–MLR model for prediction of entropy. Different internal and external validation metrics were adopted to verify the predictive performance of QSPR models. The predictive powers of the models were found to be acceptable. Thus, these QSPR models may be useful for designing new series of imidazole derivatives and prediction of their properties.