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In the present study, a novel and magnetically separable Pd−catalyst system was designed using the immobilization of PdII on Phendioxime(PDO)‐functionalized magnetic partially reduced (GO‐OMWCNT) composite (MPR (GO‐OMWCNT)/PDO/PdII). In the as‐obtained nanocomposites, the incorporation of 1D OMWCNTs and 2D graphene oxide can form a versatile 3D network with high specific surface area and synergic properties. Moreover, non‐ covalent phendioxime functionalization provides highly effective functional groups on the surface of MPR (GO‐OMWCNT) for PdII. Non‐covalent interaction carries out through π‐π stacking and hydrogen bond interactions.The catalytic activity of this nanocomposite was examined in the Suzuki–Miyaura cross‐coupling reaction. MPR (GO‐OMWCNT)/PDO/PdII composite exhibited good catalytic efficiency and obtained the products in good to excellent yield under mild aerobic conditions. Moreover, the suggested catalyst could be easily recovered magnetically and used for at least six runs without a noticeable decrease in its catalytic activity. [ABSTRACT FROM AUTHOR]

A novel magnetic core–shell Fe2O3@[proline]–CuMgAl–L(ayered)D(ouble)H(ydroxide) was designed as an efficient bifunctional catalytic system. To this end, Cu (II) was combined with Mg and Al in the LDH structure and l‐proline was intercalated between LDH layers in order to perform a straightforward synthesis of quinolines and 2H‐indazoles as two important pharmaceutical N‐aryl‐substituted heterocyclic compounds. In this regard, a facile method was employed through consecutive condensation under a mild conditions in choline azide media, which played the role of a reagent and a solvent to avoid toxic solvents and hazardous azidation reagents. These techniques provided considerable improvement in terms of using green media, reducing starting materials, reaching higher yields and offering a shorter reaction time and lower temperature. In conclusion, it was found that the catalyst could be reused five times with no significant loss of activity. [ABSTRACT FROM AUTHOR]

A highly efficient Fe3O4@VitB1–Ag(I) magnetic catalyst has been obtained using surface modification of Fe3O4. To this end, silver chloride was immobilized on Fe3O4 nanoparticles via vitamin B1 biomolecules. The synthesized biocompatible magnetic catalyst was applied in an A3‐coupling reaction in the presence of aldehyde, amine and phenyl acetylene under solvent‐free conditions and afforded the desired products in excellent yields. Also, interactions between metal and ligand in the Fe3O4@VitB1–Ag(I) were studied using theoretical calculations. [ABSTRACT FROM AUTHOR]

Vitamin B6–Pd(II) immobilized onto magnetic nanoparticles have been successfully prepared and applied for C–Xcross‐coupling reactions with aryl halides in green deep eutectic solvents. The results prove that the Fe3O4@vitamin B6–Pd(II) magnetic nanoparticles show high catalyst activity and good stability. It was also revealed that this complex can be recycled up to five times without any significant loss in catalytic activity. [ABSTRACT FROM AUTHOR]

The effects of 17 kinds of additive mixtures have been studied on refolding and aggregation of a model protein, lysozyme. Most of the prepared mixtures were efficient in inhibiting aggregation of the protein, and, surprisingly, four novel additive mixtures, i.e., lactic acid: l‐arginine, lactic acid: l‐glutamine, choline chloride: lactic acid, and imidazolium salt: β‐cyclodextrin as well as choline chloride: urea exhibited a more remarkable efficacy in suppressing aggregation. Among these, lactic acid: l‐arginine was identified as the most efficient additive, and lactic acid: l‐glutamine and choline chloride: lactic acid were inefficient to recover the enzyme activity. In contrast, choline chloride: ethylene glycol: imidazole, choline chloride: glycerol: imidazole, imidazole: betaine: ethylene glycol were found to be less effective mixtures in preventing enzyme aggregation. Totally, it was demonstrated that the protective effects of the mixtures were improved as their concentrations increased. The improvement was more remarkable for imidazolium salt: β‐cyclodextrin and choline chloride: urea, where the denatured lysozyme was reactivated and recovered up to 85% of its initial activity by enhancing their concentrations from 1 to 5% (V/V). It is suggested that such solution additives may be further employed as artificial chaperones to assist protein folding and stability. [ABSTRACT FROM AUTHOR]

One‐pot condensation of benzyl alcohol with di‐alkyl/ aryl phosphite under free solvent conditions was investigated in the presence of Fe3O4@SiO2‐Met‐Cu (II) as a recyclable heterogeneous catalyst and aqueous tert‐butyl hydroperoxide (TBHP) as the oxidant. The advantages of this protocol include good to excellent yields, easy workup, short reaction time and good reusability to 4 cycles. Also, interactions between metal and ligand in the Fe3O4@SiO2‐Metformin complex is studied by using theoretical calculations [ABSTRACT FROM AUTHOR]

In this study, the surface of silica-coated magnetic nanoparticles (Fe3O4@SiO2) were successfully functionalized by an organic ligand of 1, 4-Diazabicyclo[2.2.2]octane (DABCO)-sulfonic acid and used as a highly efficient catalyst for the synthesis of 4-aryl-NH-1, 2, 3-triazoles from the benzyl alcohol derivatives, nitromethane and sodium azide in ethanol. Furthermore, this catalyst could be recovered and reused five times without noticeable loss of activity. Fe3O4@SiO2@TCT-DABCO-SO3H nanoparticles were successfully synthesized and used as a novel, recyclable, efficient and heterogeneous catalyst for the synthesis of 4-aryl-NH-1, 2, 3-triazoles. [ABSTRACT FROM AUTHOR]