Magnetite-Supported Montmorillonite (K10) (Nanocat-Fe-Si-K10): An Efficient Green Catalyst for Multicomponent Synthesis of Amidoalkyl Naphthol†

Montmorillonite (K10) loaded on magnetite silica-coated nanoparticles was made using simple co-precipitation methods. The prepared nanocat-Fe-Si-K10 was analyzed using some techniques including field emission-scanning electron microscopy (FE-SEM), inductive coupling plasma-optical emission spectroscopy (ICP-OES), X-ray diffraction (XRD), thermo-gravimetric analysis (TGA), Fourier transmission-infrared spectra (FT-IR), energy dispersive X-ray spectroscopy (EDS), and wavelength-dispersive spectroscopy (WDX). The catalytic activity of the synthesized nanocat-Fe-Si-K10 has been examined in one-pot multicomponent transformations for the synthesis of 1-amidoalkyl 2-naphthol derivatives under solvent-free conditions. Nanocat-Fe-Si-K10 was determined to be very active, having the ability to be reused 15 times without significant loss of catalytic activity. The suggested technique has several advantages, including excellent yield, minimum reaction time, a straightforward workup, and catalyst recycling, all of which are essential green synthetic aspects

Iron Oxide-Cobalt Nanocatalyst for O-tert-Boc Protection and O-Arylation of Phenols

Efficient and general protocols for the O-tert-boc protection and O-arylation of phenols were developed in this paper using a recyclable magnetic Fe3O4-Co3O4 nanocatalyst (Nano-Fe-Co), which is easily accessible via simple wet impregnation techniques in aqueous mediums from inexpensive precursors. The results showed the catalysts were well characterized by XRD (X-ray Diffraction), ICP-AES (Inductive Coupled Plasma Atomic Emission Spectroscopy), TEM (Transmission Electron Microscopy), TOF-SIMS (Time-Of-Flight Secondary Ion Mass Spectrometry) and XPS (X-ray Photoelectron Spectroscopy). The O-tert-boc protection and O-arylation of phenols was accomplished in good to excellent yields (85–95%) and the catalyst was reusable and recyclable with no loss of catalytic activity for at least six repetitions

Iron-Oxide-Supported Ultrasmall ZnO Nanoparticles: Applications for Transesterification, Amidation, and O‑Acylation Reactions

An efficient maghemite–ZnO nanocatalyst has been synthesized via a simple coprecipitation method, where ZnO nanoparticles are uniformly decorated on the maghemite core and characterized by XRD, SEM-EDS, ICP-AES, XPS, TEM, HRTEM, and Mössbauer spectroscopy; maghemite nanoparticles are in the typical size range 10–30 nm with ultrasmall (3–5 nm) ZnO nanoparticles. A competent and benign protocol is reported for various organic transformations, namely, transesterification, amidation, and O-acylation reaction in good to excellent yields (75–97%) using magnetically separable and reusable maghemite–ZnO nanocatalyst