Formation and stabilization of colloidal ultra-small palladium nanoparticles on diamine-modified Cr-MIL-101: Synergic boost to hydrogen production from formic acid.

Ultra-small nano-sized palladium particles were successfully stabilized within the pores of diamine groups grafted open metal site metal-organic frameworks of Cr-MIL-101; coordinated diamine groups of ethylene diamine (ED) and propyl diamine (PD) on the active site of chromium units of Cr-MIL-101. The physiochemical properties of the Pd@Cr-MOFs were investigated using FTIR, XRD, SEM/EDX mapping, TEM, BET, and AAS. The Cr-MIL-101 stabilized ultra-small Pd nanoparticles, Pd@(ethylene diamine)/Cr-MIL-101, and Pd@(propyl diamine)/Cr-MIL-101, displayed catalytic activity for clean dehydrogenation of formic acid and generation of hydrogen at room temperature. The resultant Pd@ED/Cr-MIL-101 catalyst indicates high catalytic activity with turnover frequency (TOF) of 583 h-1 at 328 K, which is superior to most of the reported catalysts, including Pd@PD/Cr-MIL-101 with TOF 532 h-1. Our studies open up a new method to the design of an ultra-small metal nanoparticle for the catalytic dehydrogenation of HCOOH.

C-C and C-H coupling reactions by Fe3O4/KCC-1/APTPOSS supported palladium-salen-bridged ionic networks as a reusable catalyst.

This study investigates the potential application of an efficient, easily recoverable and reusable magnetically separable Fe3O4/KCC-1/APTPOSS nanoparticle-supported salen/Pd(ii) catalyst for C-C and C-H cross-couplings. The Fe3O4/KCC-1/APTPOSS/salen/Pd(ii) MNPs were thoroughly characterized by using TEM, FE-SEM, TGA, XRD, VSM, FT-IR, ICP-MS, and BET. This observation was exploited in the direct and selective chemical reaction of 2-acetyl-benzaldehyde with cyclopentadiene for the synthesis of pentafulvene. The recycled catalyst has been analyzed by ICP-MS showing only minor changes in the morphology after the reaction, thus confirming the robustness of the catalyst.

In vitro and in silico studies of the interaction of three tetrazoloquinazoline derivatives with DNA and BSA and their cytotoxicity activities against MCF-7, HT-29 and DPSC cell lines.

In this study, the interaction of three [1,2,3,4]tetrazolo[5,1-b]-quinazolin-8-one derivatives with salmon sperm DNA and BSA was investigated experimentally and theoretically. Fluorescence and absorption spectroscopy techniques were applied to determine the probable interaction mechanism and correlated binding constants and thermodynamic parameters. It was found that the compounds intercalate into the DNA duplex via minor groove in a moderately strong fashion with the binding constants of 104M-1. The values of binding constant for the interaction with BSA at different temperatures were also calculated to be in the range of 1.06×103-3.54×108M-1 indicating the relatively high propensity of the compounds to BSA. In vitro cytotoxicity studies on the effect of the compounds on MCF-7 and HT-29 cancerous cell lines as well as DPSC normal cell line were performed using MTT assay. It was observed that the compounds exhibited selective inhibitory effect against cancer cell growth. Moreover, each of the title compounds was separately docked to DNA and BSA using Autodock Vina as a molecular docking program. The obtained theoretical results were in good agreement with those obtained from Experimental studies.

Synthesis and characterization of ES/Cu(OH)2 nanocomposite: a novel and high effective catalyst in the green synthesis of pyrano[4,3-b]pyrans.

The eggshell (ES) supported Cu(OH)2 nanoribbons containing 8 wt.% Cu(2+) as a novel and heterogeneous catalyst was synthesized by simply adding an aqueous solution of CuSO4 on the eggshell support at ambient temperature. The nanocomposite system was characterized by scanning electron microscopy (SEM), transition electron microscopy (TEM), X-ray diffraction (XRD), energy dispersive X-ray (EDX), thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) spectroscopy and BET surface area analysis. Also, electrochemical impedance spectroscopy was used as powerful techniques for an electrical conductivity investigation. The loading of copper on the mesoporous supports provides high catalytic activity for the green synthesis of pyrano[4,3-b]pyrans. The reaction proceeds to completion in 5 min with excellent yields of 93-97%. The suggested strategy for synthesis of pyrano[4,3-b]pyrans is very interesting due to application of a green and low cost composite as a heterogeneous catalyst and its simplicity in preparation, short reaction time, high yields without further purification and high reusability without any loss of catalytic activity.

Microwave-assisted multicomponent reactions of alkyl bromides: synthesis of thiophene derivatives.

A series of thiophene derivatives were synthesized via one-pot multicomponent reactions of alkyl bromides, aroyl or alkanoyl isothiocyanates, 1,3-dicarbonyl compounds and secondary amines under microwave irradiation at 80°C. Particularly valuable features of this method include high yields of products, broad substrate scope, short reaction time and straightforward procedure.

One-pot and efficient synthesis of triazolo[1,2-a]indazole-triones via reaction of arylaldehydes with urazole and dimedone catalyzed by silica nanoparticles prepared from rice husk.

A novel synthesis of triazolo[1,2-a]indazole-1,3,8-trione derivatives by reaction of urazole, dimedone and aromatic aldehydes under conventional heating and microwave irradiation and solvent-free conditions using silica nanoparticles prepared from rice husk ash as catalyst is described. The new method features high yields, multicomponent reactions and environmental friendliness.

Synthesis of oxime phosphoranes from reaction between triphenylphosphine and acetylenic esters in the presence of oxime derivatives.

A new one-pot, simple and effective procedure is presented for the preparation of O-containing phosphorus ylides by the Michael addition reaction of N-methylpyrrole-2-carbaldehydoxime, pyridin-2-carbaldehydoxime or acetophenonoxime with acetylenic esters.