An efficient and heterogeneous novel magnetic silica-coated picolylaminecopper complex [Fe3O4@SiO2@GP/Picolylamine-Cu­(II)] was synthesized, characterized, and employed as a magnetically recoverable nanocatalyst in Biginelli condensation for the preparation of biologically active 3,4-dihydropyrimidinones. Fe3O4@SiO2@GP/Picolylamine-Cu­(II) was synthesized easily using chemical attachment of the picolylaminecompound on Fe3O4@SiO2@GP, followed by treatment with copper salt in ethanol under reflux conditions. Fe3O4@SiO2@GP/Picolylamine-Cu­(II) was affirmed by various analyses such as Fourier transform infrared, thermogravimetric analysis, X-ray diffraction, vibrating-sample magnetometry, field-emission scanning electron microscopy, transmission electron microscopy, DLS, inductively coupled plasma, energy-dispersive X-ray spectrometry, X-ray photoelectron spectroscopy, and Brunauer–Emmett–Teller. The resulting catalyst system was successfully used in the Biginelli reaction through a variety of compounds such as aromatic aldehyde, urea, and ethyl acetoacetate under solvent-free conditions or ethylene glycol at 80 °C and yielded the desired products with high conversions with powerful reusability. The current approach was convenient and clean, and only 0.01 g of the catalyst could be used to perform the reaction. The easy work-up procedure, gram-scale synthesis, usage of nontoxic solvent, improved yield, short reaction times, and high durability of the catalyst are several remarkable advantages of the current approach. Also, the Fe3O4@SiO2@GP/Picolylamine-Cu­(II) nanocatalyst could be recycled by an external magnet for eight runs with only a significant loss in the product yields.

In the present work, based on a convergent protocol, we synthesized proline-Cu complex based 1,3,5-triazine coated on Fe3O4 magnetic nanoparticles as a green and recyclable nanocatalyst by an inexpensive and simple procedure. Then, fully specified by Fourier transform infrared spectroscopy (FT-IR), we pursued field emission scanning electron microscopy (FESEM), vibrating sample magnetometry (VSM), powder X-ray diffraction (PXRD), energy dispersive X-ray analysis (EDX), thermogravimetric analysis (TGA), and Brunauer–Emmet–Teller (BET) and inductively coupled plasma (ICP) analysis. The catalytic movement of the synthesized nanocatalyst underwent successful investigation in the Knoevenagel condensation through malononitrile as well as various aldehydes in H2O as a green solvent at room temperature. The high efficiency, short reaction time, ecofriendly properties, and easy workup can be considered the major benefits of the current method. Also, the separation of the nanocatalyst was easily performed by an external magnet and applied again for eight fresh runs with no considerable loss of catalytic activity.

A novel and recyclable core–shell magnetic NiII-picolylamine/TCT/APTES@SiO2@Fe3O4 with high specific area was introduced for the synthesis of pyridine derivatives.

A novel catalyst has been afforded by attaching of a Cu­(proline)2 complex to magnetic nanoparticles through cheap, simple, and readily available chemicals. This catalyst was characterized by Fourier transform infrared, energy-dispersive X-ray, X-ray diffraction, vibrating-sample magnetometry, transmission electron microscopy, scanning electron microscopy, and inductively coupled plasma analyses. The catalytic activity of the Fe3O4@NH2@TCT@HProCu nanocatalyst was investigated in a green and effective synthesis of pyran derivatives in high yields by applying three-component reactions of malononitrile, dimedone, and aldehydes in ethanol. Conversion was high under optimal conditions. The obtained nanocatalyst could be easily separated from the mixture of the reaction and was recyclable nine times via a simple magnet without considerable reduction of its catalytic efficiency. Operational simplicity, high product yields, environmental friendliness, ecofriendliness, economical processing, and easy workup are the features of this methodology.

Magnetic nanoparticles have been proved as a tremendously powerful synthetic tool to achieve a milder process for the organic transformations and also suggested many potentialities in biomedical applications. They have an important role in the human health, environment protection, and energy resource management. Excellent reusability, easy separation of nanosized catalysts, and stability are the significant advantages of these catalysts. Hence, detailed studies on their synthesis mechanism for both chemical transformations and biomedical applications are crucial. In this review, we described a brief introduction of the dendrimers and various methods that are used for their synthesis, followed by the discussion of the syntheses and structures of magnetic nanodendrimers and their catalytic application in organic synthesis. We accordingly embarked on the studies on their synthesis mechanism for chemical transformations especially their surface modification since 2001.