Application of Coordination Compounds with Transition Metal Ions in the Chemical Industry-A Review

This publication presents the new trends and opportunities for further development of coordination compounds used in the chemical industry. The review describes the influence of various physicochemical factors regarding the coordination relationship (for example, steric hindrance, electron density, complex geometry, ligand), which condition technological processes. Coordination compounds are catalysts in technological processes used during organic synthesis, for example: Oxidation reactions, hydroformylation process, hydrogenation reaction, hydrocyanation process. In this article, we pointed out the possibilities of using complex compounds in catalysis, and we noticed what further research should be undertaken for this purpose.

Sulfidation modulates the toxicity of biogenic copper nanoparticles

First report to show sulfidation reduces CuNP toxicity in vivo. Sulfidation lowered oxidative stress and liver pathology, protected biochemical components, prevented micronucleus formation – strategy for reducing environmental impact of nanoparticles.

Hyperhydrophilic three-dimensional crosslinked beads as an effective drug carrier in acidic medium: adsorption isotherm and kinetics appraisal

Langmuir adsorption isotherm demonstrates monolayer drug loading with hyperhydrophilic three-dimensional crosslinked polymers. Furthermore, the pseudo order kinetics were also evaluated.

Ligand-free reusable nano copper oxide-catalyzed synthesis of 3-amino-1,4-diynes

The synthesis of 3-amino-1,4-diynes has been developed by the two-component coupling of N,N-dimethyl formamide dimethyl acetal with terminal alkynes using CuO nanoparticles as an efficient catalyst under mild reaction conditions.

In situ generation of palladium nanoparticles: ligand-free palladium catalyzed pivalic acid assisted carbonylative Suzuki reactions at ambient conditions

Highly selective carbonylative Suzuki reactions of aryl iodides with arylboronic acids using an in situ generated nanopalladium system furnished products in high yields. The reactions were performed under ambient conditions and in the absence of an added ligand. The key to success is the addition of pivalic acid, which can effectively suppress undesired Suzuki coupling. The synthesis can be easily scaled up, and the catalytic system can be reused up to nine times. The nature of the active catalytic species are discussed.

A facile route to synthesize casein capped copper nanoparticles: an effective antibacterial agent and selective colorimetric sensor for mercury and tryptophan

A simple method was developed for the synthesis of copper nanoparticles (CuNPs) with relatively high concentration by using casein as a capping agent.

β-Sitosterol-d-glucopyranoside isolated from Desmostachya bipinnata mediates photoinduced rapid green synthesis of silver nanoparticles

A sunlight-induced synthesis of silver nanoparticles using β-sitosterol-d-glucopyranoside, a bio-surfactant isolated from the Indian sacred grass Desmostachya bipinnata.

Efficient one-pot synthesis of propargylamines catalysed by gold nanocrystals stabilized on montmorillonite

Size selective Au⁰-nanoparticles were generatedin situin the nanopores of montmorillonite and applied in the one-pot, three-component coupling of an aldehyde, an amine and an alkyne to synthesize propargylamines.

Aerobic synthesis of biocompatible copper nanoparticles: promising antibacterial agent and catalyst for nitroaromatic reduction and C–N cross coupling reaction

Herein, we report the synthesis of copper nanoparticles at ambient conditions using biopolymer, pectin, as a protecting agent and hydrazine as a reducing agent.

Chitosan coating of copper nanoparticles reduces in vitro toxicity and increases inflammation in the lung

Despite their potential for a variety of applications, copper nanoparticles induce very strong inflammatory responses and cellular toxicity following aerosolized delivery. Coating metallic nanoparticles with polysaccharides, such as biocompatible and antimicrobial chitosan, has the potential to reduce this toxicity. In this study, copper nanoparticles were coated with chitosan using a newly developed and facile method. The presence of coating was confirmed using x-ray photoelectron spectroscopy, rhodamine tagging of chitosan followed by confocal fluorescence imaging of coated particles and observed increases in particle size and zeta potential. Further physical and chemical characteristics were evaluated using dissolution and x-ray diffraction studies. The chitosan coating was shown to significantly reduce the toxicity of copper nanoparticles after 24 and 52 h and the generation of reactive oxygen species as assayed by DHE oxidation after 24 h in vitro. Conversely, inflammatory response, measured using the number of white blood cells, total protein, and cytokines/chemokines in the bronchoalveolar fluid of mice exposed to chitosan coated versus uncoated copper nanoparticles, was shown to increase, as was the concentration of copper ions. These results suggest that coating metal nanoparticles with mucoadhesive polysaccharides (e.g. chitosan) could increase their potential for use in controlled release of copper ions to cells, but will result in a higher inflammatory response if administered via the lung.

A sunlight-induced rapid synthesis of silver nanoparticles using sodium salt of N-cholyl amino acids and its antimicrobial applications

Aqueous solution containing two additives, silver nitrate (AgNO(3)) and sodium salt of N-cholyl amino acid were irradiated by sunlight for the synthesis of spherical shaped AgNPs without the need for an additional stabilizer or capping agent. Variations of N-cholyl amino acid concentration provided good control over the morphology of the AgNPs, while the carboxylate group of bile salt reduced the Ag(+) ions and the amide group binds strongly to the surface of the NPs. The optical properties, morphology of the AgNPs were characterized by UV-visible, transmission electron microscopy (TEM) and dynamic light scattering (DLS) studies. The interaction of N-cholyl amino acid on the AgNPs surface was studied using cyclic voltammetry and FT-IR techniques. The reduction process was completed within 5 min and the synthesized AgNPs were stable for more than 6 months. The possible mechanism of N-cholyl amino acid on the reduction and stabilization of AgNPs is also discussed. The antimicrobial activity of N-cholyl amino acid capped AgNPs against Escherichia coli, Staphylococcus aureus and Pseudomonas aeroginosa using Mueller Hinton broth and the antifungal activity against Candida albicans, Candida krusei and Candida tropicalis using RPMI broth were determined by MIC studies as per CLSI guidelines.

Copper nanoparticle-catalyzed carbon-carbon and carbon-heteroatom bond formation with a greener perspective

The carbon-carbon and carbon-heteroatom bond formations constitute the backbone of organic synthesis and have been widely used in the synthesis of natural products and useful compounds. Because of growing environmental concern, more attention has been focussed on the development of greener methods. Copper is environment-friendly and comparatively inexpensive. Although the use of copper salts in catalysis has been known since the last century, this area of research has been less explored compared to other metals, such as palladium, magnesium, and zinc. This review highlights the general features of nanoparticles as catalysts with particular reference to copper and the recent developments in the copper(0) nanoparticle-catalyzed C(aryl)-C(aryl/alkynyl), C(aryl)-N, C(aryl)-O, C(aryl)-S, and C(aryl)-Se bond formations and related reactions. The mechanisms of the reactions have been outlined and discussed with respect to the active catalytic species and possible intermediates. The scope, limitations, and green aspects of the reactions have also been highlighted. The convenient methods of preparation of copper nanoparticles and their characterization are described.

Silica-dendrimer core-shell microspheres with encapsulated ultrasmall palladium nanoparticles: efficient and easily recyclable heterogeneous nanocatalysts

We report the synthesis, characterization, and catalytic properties of novel monodisperse SiO(2)@Pd-PAMAM core-shell microspheres containing SiO(2) microsphere cores and PAMAM dendrimer-encapsulated Pd nanoparticle (Pd-PAMAM) shells. First, SiO(2) microspheres, which were prepared by the Stöber method, were functionalized with vinyl groups by grafting their surfaces with vinyltriethoxysilane (VTS). The vinyl groups were then converted into epoxides by using m-chloroperoxybenzoic acid. Upon treatment with amine-terminated G4 poly(amidoamine) (PAMAM) dendrimers, the SiO(2)-supported epoxides underwent ring-opening and gave SiO(2)@PAMAM core-shell microspheres. Pd nanoparticles within the cores of the SiO(2)-supported PAMAM dendrimers were synthesized by letting Pd(II) ions complex with the amine groups in the cores of the dendrimers and then reducing them into Pd(0) with NaBH(4). This produced the SiO(2)@Pd-PAMAM core-shell microspheres. The presence of the different functional groups on the materials was monitored by following the changes in FTIR spectra, elemental analyses, and weight losses on thermogravimetric traces. Transmission electron microscopy (TEM) images showed the presence of Pd nanoparticles with average size of 1.56 ± 0.67 nm on the surface of the monodisperse SiO(2)@Pd-PAMAM core-shell microspheres. The SiO(2)@Pd-PAMAM core-shell microspheres were successfully used as an easily recyclable catalyst for hydrogenation of various olefins, alkynes, keto, and nitro groups, giving ~100% conversion and high turnover numbers (TONs) under 10 bar H(2) pressure, at room temperature and in times ranging from 10 min to 3 h. In addition, the SiO(2)@Pd-PAMAM core-shell microspheres were proven to be recyclable catalysts up to five times with barely any leaching of palladium into the reaction mixture.