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The synthesis of an efficient heterogeneous nanocatalyst was prepared by the anchoring of palladium complex on the surface of an imidazolium‐based ionic liquid‐functionalized Fe3O4 (Pd‐imidazolium@Fe3O4 NPs). The nanocatalyst, Pd‐imidazolium@Fe3O4 NPs, was characterized by Raman, X‐ray diffraction (XRD), thermogravimetric analysis (TGA), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy‐dispersive X‐ray spectroscopy (EDX), fourier transform infrared (FT‐IR), inductively coupled plasma (ICP), and vibrating sample magnetometer (VSM) techniques. The catalytic performance of this novel nanocatalyst was evaluated in the Heck––Mizoroki and Suzuki–Miyaura cross‐coupling reactions under mild conditions using PEG‐400 as a green and biodegradable solvent. The nanocatalyst exhibited high catalytic activity for both cross‐coupling reactions. Furthermore, this stable nanocatalyst can be easily removed and recovered from the reaction mixture and reused for at least eight consecutive cycles without a discernible decrease in the catalytic activity. Also, the recovered Pd‐imidazolium@Fe3O4 NPs was characterized by FT‐IR, XRD, scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, and atomic absorption spectroscopy techniques. [ABSTRACT FROM AUTHOR]

Ammonium chlorochromate supported onto alumina efficiently regenerates carbonyl compounds from their corresponding semicarbazones and phenylhydrazones under classical heating in non-aqueous conditions and microwave irradiation in solvent-free system.

The synthesis of a new palladium(II) complex, [Pd(AMTTO)(PPh3)2] (1, H2AMTTO = 4-amino-6-methyl-1,2,4-triazine-3-thione-5-one), is reported. Complex 1 has been characterized by FT-IR, 1H NMR and 31P NMR spectroscopy as well as mass spectrometry. Furthermore, its molecular structure and thermal stability have been investigated via X-ray and thermogravimetric analyses. The crystal structure of 1 revealed that the twofold deprotonated ligand acts as a bidentate chelating one and coordinates to the metal ion through its sulfur and nitrogen atoms in a cis-arrangement. The biological activity including anticancer and antibacterial activity of the ligands and complex 1 was studied. The IC50 value of the latter against MCF-7 was 0.06 mM. This is while carboplatin (as a standard anticancer drug) exhibited no cytotoxicity at the same concentration. Moreover, the synthesized Pd(II) complex displayed potent antimicrobial activity against Gram-positive (ATCC 6538) and Gram-negative (ATCC 25922) bacterial strains. [ABSTRACT FROM AUTHOR]

A novel mononuclear palladium(II) complex, [Pd(L)Cl2]·DMF (1·DMF, L = 1,4-bis(5-amino-1,3,4-thiadiazol-2-sulfanyl-methyl)benzene), has been synthesized and characterized by elemental analysis, FT-IR and 1H NMR spectroscopy and single-crystal X-ray diffraction. On the basis of the molecular structure, in 1·DMF, a ligand acts as a bidentate chelating one using its endocyclic nitrogen atoms. The biological activities of the free ligand and its palladium complex including cytotoxic activity towards the human colon cancer cell line (HCT-116) and antibacterial activity against one Gram-negative strain (Escherichia coli (ATCC 25922)) and one Gram-positive strain (Staphylococcus aureus (ATCC 6538)) have been examined. The IC50 value of 1·DMF against HCT-116 was 500 μM, which is much higher than that reported for cisplatin, and hence, the compound exhibited low anticancer efficacy compared to cisplatin. However, it exhibited excellent antibacterial activities against both Gram-negative as well as Gram-positive bacterial microorganisms. Furthermore, the thermal stability of complex 1·DMF was studied by thermal gravimetric analysis (TGA). The resulting product was characterized as highly pure PdO nanoparticles (mean crystallite size: 39 nm) by using a series of techniques including powder XRD, EDAX, and SEM. [ABSTRACT FROM AUTHOR]

Fuberidazole has been successfully immobilized onto nano‐Fe3O4 supported (3‐chloropropyl)trimethoxysilane (3‐CPTS) leading to a novel functionalized magnetic nanoparticle (FB/MNP). The Pd(0) complex, Pd‐FB/MNP, was prepared by grafting Pd (OAc)2 on FB/MNP and subsequent reduction of a synthesized Pd (II) complex using NaBH4. Pd‐FB/MNP has been characterized by FT‐IR, SEM, TGA, XRD, ICP, EDS, BET and VSM. The Pd(0) complex proved to be an efficient phosphine‐ and halide‐free recyclable heterogeneous catalyst for Suzuki as well as for Stille C‐C coupling reactions showing high catalytic activity (up to 98%). Its catalytic activity in both reactions has been studied in PEG‐400 as a green solvent. Besides, the selectivity of aryl iodide and aryl bromide over aryl chloride is observed during the C‐C coupling reaction. The catalyst could be recovered easily from the reaction mixture using an external magnet device and recycled several times without considerable loss in activity. Additionally, the results of a palladium leaching test of the nano‐catalyst demonstrate that no leaching of Pd took place during the C‐C coupling process making the procedure environmentally friendly. [ABSTRACT FROM AUTHOR]

The reaction of ferrocene 2-carboxaldehyde with 4-Amino-6-methyl-1,2,4-triazine-3-thione-5-one ( AMTTO ) in a molar ratio 1:1 in dry ethanol led to the formation of ( E )-4-((2-ferrocenylidene)amino)-6-methyl-3-thioxo-3,4-dihydro-1,2,4-triazin-5(2H)-one Schiff base ( FTS ). FTS has been characterized by elemental analysis, IR-, 1 H NMR-spectroscopy and mass spectrometry as well as single crystal X-ray diffraction. The electrochemical potential of FTS has also been studied. Solventless thermolysis of FTS at 540, 600 and 900 °C in air led to the formation of α -Fe 2 O 3 nanostructures. The resulting hematites were characterized by X-ray powder diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX) and scanning electron microscopy (SEM). Magnetic properties of the products from solventless thermolysis of FTS were investigated using vibrating sample magnetometer (VSM). [ABSTRACT FROM AUTHOR]

A cadmium(II) complex formulated as, [Cd(amp)2(O2NO)(ONO2) (OH2)2]·H2O (1), (amp = 2-aminopyrimidine) has been synthesized and characterized by elemental analysis and IR spectroscopy as well as by X-ray crystal structure analysis. Its thermal stability by TGA/DTA methods. Each cadmium(II) ion is seven coordinated in adistorted pentagonal bipyramidal geometry. A wide range of hydrogen bandings (of the O–H…O, N–H…O, and N–H…N types) and π-π stacking interactions are also present in the crystal structure. This arrangement leads to the formation of a 3D supramolecular structure. [ABSTRACT FROM AUTHOR]

The synthesis, characterization, and thermal decomposition behaviour of the oxalato-bridged copper(II) coordination polymer [Cu2(C2O4)(L)2Cl2(MeOH)2] n ( 1) (L = 3,5-dimethyl-1 H-pyrazole) is reported. Complex 1 is prepared in a straightforward fashion by a one-pot reaction of acetylacetone, thiosemicarbazide, oxalic acid and copper(II) chloride in a molar ratio of 2:2:1:2. Complex 1 was characterized by means of FT-IR spectroscopy, mass spectrometry and elemental analysis as well as single-crystal X-ray diffraction. Furthermore, the electrochemical behavior of 1 was investigated in DMSO by cyclic voltammetry. The thermal stability of complex 1 was studied by thermal gravimetric (TG) and differential thermal analyses (DTA). Solventless thermolysis of complex 1 at 550 °C and 1000 °C under air afforded copper oxide nanoparticles and nanosheets, respectively. The CuO nanostructures were characterized by using a series of techniques including FT-IR, UV/Vis, XRD, XPS, EDAX, and SEM. [ABSTRACT FROM AUTHOR]

Treatment of an aqueous solution of dipicolinic acid (dipicH2) and 2-aminopyrazine (apyz) with Cu(NO3)2 · 3H2O or ZnCl2 (in molar ratio 1 : 1 : 1) led to formation of dinuclear complexes, [M2(H2O)4(dipic)2(µ-apyz)] (M = Cu (1) and Zn (2)). Both complexes were characterized by elemental analyses, IR, and UV-Vis spectroscopy. Their molecular and crystal structures were determined by X-ray crystal structure analysis and their thermal stabilities were confirmed by TGA/DTA methods. Complex 1 crystallizes in the triclinic P-1 space group, while 2 crystallizes in the monoclinic P21/c space group. The dinuclear complexes are analogous and composed of two metal ions bridged by 2-aminopyrazine. Each M(II) is coordinated by one nitrogen atom and two oxygen atoms of tridentate dipicolinate, one heterocyclic nitrogen of 2-aminopyrazine, and two coordinated water molecules. The resulting geometry for the MN2O4 coordination environment can be described as distorted octahedral. Extensive hydrogen-bonding interactions involving all water ligands, dipicolinate oxygen atoms, and amino groups further stabilize the complex units by linking them to form 3-D networks for 1 and 2. [ABSTRACT FROM AUTHOR]

The reaction of 4-amino-6-methyl-5-oxo-3-thioxo-2H-1,2,4-triazine, (AMTTO, [1]), and 4-amino-5-methyl-3-thioxo-2H-1,2,4-triazole, (AMTT, [2]), with various aldehydes under classical heating and microwave irradiation in a solvent-free system resulted in the formation of the corresponding imines 3a–e and 4a–d. The compounds were characterized by their spectroscopic data and elemental analysis. Compound 3a was also characterized by X-ray diffraction studies. Crystal data for 3a at -80°C: triclinic, space group P-1, a = 796.7(2), b = 844.8(2), c = 1073.1(2) pm, α = 88.44(2)°, β = 76.59(2)°, γ = 63.42(2)°, Z = 2. [ABSTRACT FROM AUTHOR]

A new method for the preparation of imidazo[1,2- c ]pyrimidines is described. [ABSTRACT FROM AUTHOR]

An efficient and convenient conversion of aldoximes and ketoximes to the corresponding carbonyl compounds with tetrameric DABCO–bromine complex is reported. [ABSTRACT FROM AUTHOR]

Treatment of 2-chloro-4-propargyloxo-5-nitro-6-methylpyrimidine with conc. sulfuric acid gave a novel heterocyclic system 2,3-dihydro-3-methylene-7-methyl-8-nitro-5H-oxazolo [3,2-c]pyrimidine-5-one ( 5 ) [ABSTRACT FROM AUTHOR]

Substituted 6-chloro-pyrimido[4,5- e ][1,3,4] thiadiazine was converted to the corresponding 6-hydrazino derivative by treatment with hydrazine hydrate in DMF/Et 3 N. The latter was converted to various substituted [1,2,4]triazino[1,2- a ] pyrimido[4,5- e ][1,3,4]thiadiazines. [ABSTRACT FROM AUTHOR]