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2-Thiazolylhydrazonomalononitrile (1) was used as key intermediate for the synthesis of polyfunctionally substituted heterocycles (e.g. pyridazine, tetrazole, pyrimidines, 1,5-benzo diazepine, benzoimidazo[1,2-a]pyrimidine, triazolo[4,3-a]pyrimidine, pyrazole, pyrazolo[1,5-a]triazines, pyrazolo[1,5-a]pyrimidine and 1,5-benzoxazocine) incorporating thiazole moiety via its reactions with some carbon and nitrogen nucleophiles. Structures of the newly synthesized compounds were established by elemental analysis and spectral data. The mechanistic aspects for the formation of the new compounds were also discussed.

A one-pot, tandem oxidation–Wittig procedure has been developed in which the reacting components are generated in situ from alcohols, triphenyl phosphine, and ethyl bromoacetate using barium manganate as a mild oxidizing agent without the addition of an external base.

Graphene (GR) and its derivatives are promising materials on the horizon of nanotechnology and material science and have attracted a tremendous amount of research interest in recent years. The unique atom-thick 2D structure with sp(2) hybridization and large specific surface area, high thermal conductivity, superior electron mobility, and chemical stability have made GR and its derivatives extremely attractive components for composite materials for solar energy conversion, energy storage, environmental purification, and biosensor applications. This review gives a brief introduction of GR's unique structure, band structure engineering, physical and chemical properties, and recent energy-related progress of GR-based materials in the fields of energy conversion (e.g., photocatalysis, photoelectrochemical water splitting, CO2 reduction, dye-sensitized and organic solar cells, and photosensitizers in photovoltaic devices) and energy storage (batteries, fuel cells, and supercapacitors). The vast coverage of advancements in environmental applications of GR-based materials for photocatalytic degradation of organic pollutants, gas sensing, and removal of heavy-metal ions is presented. Additionally, the use of graphene composites in the biosensing field is discussed. We conclude the review with remarks on the challenges, prospects, and further development of GR-based materials in the exciting fields of energy, environment, and bioscience.

The palladium catalyzed one-pot synthesis of isoxazoles and pyrazoles from aryl iodides, terminal alkynes, chromium hexacarbonyl and hydroxylamine hydrochloride or aqueous hydrazine solution is described. The Sonogashira carbonylative coupling intermediate was trapped in situ by hydroxylamine hydrochloride or aqueous hydrazine to deliver isoxazoles or pyrazoles, respectively, in high yields. This efficient method proceeds at atmospheric pressure and moderate temperature and does not require the use of copper, phosphine ligands or gaseous carbon monoxide.

This review summarizes results from a literature survey concerning the synthesis and reactions of 4-amino-3-mercapto-1,2,4-triazine-5-ones reported by research groups from 1983 to mid. 2015.

A novel Pd-catalyzed reductive carbonylation of iodoranes under phosphine-free conditions and Fe(CO)5 as CO source is developed.

Crystals of the one-dimensional compound (PipH2)2[PbI5]I·H2O (Pip: piperazine) are obtained by slow evaporation of a solution containing a 1:2 molar mixture of PbI2 and piperazine in a 1:1 molar mixture of EtOH and DMF (25 °C, several weeks).

Aliphatic (Ia) and benzylic alcohol (Ic) as well as their analogous thiols are subjected to the reaction with phosphites (IIa)/(IIc) under optimized conditions A) to produce synthetically important phosphonates.

In this article we report a non-odorous protocol for the high yield formation of aryl–alkyl sulfides by the reaction of aryl iodides, bromides and boronic acids with elemental sulfur and electron-deficient alkenes, catalyzed by copper ferrite nanoparticles. The catalyst was easily separated using an external magnetic bar and recycled for subsequent runs, its catalytic activity being preserved.

The convenient nickel-catalyzed carbonylative coupling of aryl iodides with Ph3SnCl or Ph3SnOEt for synthesis of unsymmetrical diaryl ketones under phosphine-free condition is reported. The reaction occurs efficiently in the presence of Cr(CO)6 as an easy handling solid source of carbon monoxide at atmospheric pressure and 100 °C in DMF under air to deliver the desired ketones in high yield.

K0.405Bi0.865AsO4 is prepared via solid state reaction of a 3:3:4 = K:Bi:As molar mixture of K2CO3, Bi2O3, and NH4H2AsO4 (850 °C, 1 month; cooling to 25 °C at a rate of 5 K/h).

This study describes our findings on a novel and cheap NiCl2 catalytic system under ligand-free conditions for the efficient thiocarbonylation, alkoxycarbonylation and amidocarbonylation reactions of aryl iodides in the presence of Cr(CO)6 as the solid source of carbon monoxide under air. A variety of aryl iodides tolerated the reaction conditions and structurally different thiols, alcohols and amines were used efficiently. The corresponding thioesters, esters and amides were obtained in good to excellent yield at atmospheric pressure under mild reaction conditions.

In this study, we have employed dithiooxamide, a solid, odorless, and commercially available compound, as a sulfur surrogate for the preparation of dialkyl sulfides from available alkyl halides in high yields. This sulfur transfer agent was also used for a copper-catalyzed high-yielding preparation of diaryl sulfides from their available aryl halides and for the preparation of thia-Michael adducts in high yields. All the reactions were performed under odorless conditions in wet PEG200 (PEG = polyethylene glycol), which is an eco-friendly, safe, and recoverable solvent. The protocols were easily applicable to large-scale operation.

CsCrAs2O7 is prepared by calcination of a stoichiometric mixture of Cs2CO3, Cr2O3, and NH4H2AsO4 (porcelain crucible, 1023 K, 4 d; cooling to 923 K at a rate of 5 K/d).

Single crystals of alluaudite-type K0.13Na3.87MgMo3O12 are prepared by solid state reaction of Na2CO3, K2CO3, (NH4)2Mo4O13, and Mg(NO3)2 (Na:K:Mo:Mg = 3.8:0.2:3:1, air, porcelain crucible, 700 °C, 7 d; cooling to 600 °C with a rate of 5 °C/d; quenching to 25 °C).

Single crystals of the hybrid compound (H2dabco)2 [Sb2Cl10]·H2O are obtained by stirring a mixture of DABCO and SbCl3 in HCl at 353 K followed by slow evaporation of the solvent (25 °C, 2 weeks).

A Smiles rearrangement—elimination sequence is developed which allows the preparation of various title compounds without isolation of the intermediate hemiketal.

A reusable ligand-free palladium catalyzed phosphonation of aryl iodides, bromides and chlorides with trialkylphosphites is described for the first time in neat water. The aryl phosphonates are obtained in good to excellent yields. The reaction can be also performed with Ni(II) with longer reaction time. The role of tetrabutylammonium bromide in this reaction as reducing agent for generation of Pd(0) at room temperature is also demonstrated. Pd(0)/TBAB was easily reused for three runs without decreasing the efficiency.

Aminocarbonylation of aryl halides (I) with dimethylformamide (II) as the source of the carbonyl group is accomplished under title conditions.

Sodium N,N-diethyldithiocarbamate which serves as sulfur source is prepared in situ using CS2 in combination with NaOH and diethylamine.

A series of fluorine and non-fluorine-substituted C-glucosylidenes (III)/(IV) is synthesized as mixtures of (E)/(Z)-isomers via a modified Julia olefination.

Silica diphenylphosphinite (SDPP) can be easily obtained through direct phosphorylation of silica gel. Further reaction of SDPP with Pd(II) produces nano Pd(0)/SDPP. This nano Pd(0) catalyst exhibits excellent reactivity for the C-O and C-S arylation of different aryl iodides, bromides and chloride with phenols and thiophenols. This heterogeneous catalyst shows excellent recyclability and can be easily recovered and reused for several runs. Copyright © 2013 John Wiley & Sons, Ltd.

The compounds (IIIc) and (IIId) show antimicrobial activity against a broad spectrum of bacteria (S.

This describes new nano-Pd catalysts generated in situ from PdCl2 and bis-diphenylphosphorylated PEGs.

Triphenyltin chloride is used as phenyl group source for the Cu-catalyzed phenylation of primary and secondary amines, phenols, and thiols.

Both the protecting groups as well as the presence of BF3·Et2O influence yield and E/Z selectivity of the reaction.

Ph 3 P, Br 2 , and ammonium acetate are used for the in situ generation of Ph 3 P(OAc) 2 , which was characterized by different NMR techniques. The Ph 3 P(OAc) 2 generated was used as a novel and efficient reagent for the acetylation of alcohols and thiols in acetonitrile at room temperature under homogeneous conditions. This reaction was also performed under heterogeneous conditions using 1,3,2,4-diazadiphosphetidine as an easily prepared, stable, and heterogeneous P(III) compound.

The quest for higher density information storage has led to the investigation of Single-Molecule Magnets (SMMs) as potential molecules to be applied in materials such as hard discs. In order for this to occur, one must first design metal complexes which can retain magnetic information at temperatures where these applications become possible. This can only be achieved through answering and understanding fundamental questions regarding the observed physical properties of SMMs. While mononuclear lanthanide complexes have shown promise in obtaining high energy barriers for the reversal of the magnetisation they are limited to Single-Ion Magnet behaviour intrinsic to one metal centre with a limited number of unpaired electrons. As a way of increasing the effective anisotropic barrier, systems with higher nuclearity have been sought to increase the spin ground state of the molecule. Dinuclear complexes are presented as key compounds in studying and understanding the nature of magnetic interactions between metal ions. This tutorial review will span a number of dinuclear 4f complexes which have been critical in our understanding of the way in which lanthanide centres in a complex interact magnetically. It will examine key bridging moieties from the more common oxygen-based groups to newly discovered radical-based bridges and draw conclusions regarding the most effective superexchange pathways allowing the most efficient intracomplex interactions.

A simple and efficient method is described for aminocarbonylation of aryl, benzyl, and styryl iodides and bromides using the in situ generated molybdenum tetracarbonyl norbornadiene [Mo(CO)4(nbd)] complex as a suitable source of carbon monoxide.

Conductive polymers (CPs) are classified as materials which exhibit highly reversible redox behavior and the unusual combined properties of metal and plastics. CPs, due to their multifunctionality, ease of synthesis and their stability, have attracted more attentions in different fields of research, including sample preparation. CPs along with several commercial hydrophilic sorbents, are alternative to the commercially available hydrophobic sorbents which despite their high specific surface areas, have poor interactions and retentions in the extraction of polar compounds. This review covers a general overview regarding the recent progress and new applications of CPs toward their synthesis and use in novel extraction and microextraction techniques including solid phase microextraction (SPME), electrochemically controlled solid-phase microextraction (EC-SPME) and other relevant techniques. Furthermore the contribution of nano-structured CPs in these methodologies is also reviewed.

A highly efficient and green procedure for the synthesis of α-amino nitriles (IV) (12 examples) via a one-pot three-component reaction is given.

4,4′-Azopyridine 1a and 5,5′-dimethyl-3,3′-azoisooxazole 1e are used for the efficient, direct, and selective conversion of aliphatic alcohols into their corresponding disulfides in high yields under Mitsunobu conditions in combination with PPh3 and NH4SCN. The reaction with 1a occurs homogeneously, and 1e heterogeneously. In both reactions, the produced N-cyanohydrazines are isolated and reoxidized to the corresponding azo compounds easily.

CeO2 is found to be highly efficient for the three-component reactions to yield 1,2-disubstituted pyrrolidines.

The title heterogeneous catalyst works under mild conditions and is especially useful for the selective cross-coupling of hydroxyl-substituted aryl iodides, e.g. (Ia)—(Ic).

A simple method for the synthesis of aminoaryl and heteroaryl thiocyanates (III) and (V) is given using 2,2′-azobis(benzothiazole) as oxidant.

A cheap and convenient method for the phosphorylation of silica gel is developed and the material is used to immobilize Pd(0)-nanoparticles.

The ionic liquids (5 examples) are found to act as base, ligand, reducing agent and media for the title reactions of aryl iodides and bromides.

Solid-phase microextraction (SPME) is a fast, solvent-free technique, which, since its introduction in the 1990s, has been increasingly applied to sample preparation in analytical chemistry. Conventional SPME fibers are fabricated by making a physical bond between the usual silica substrate and the polymeric coatings. However, some applications are limited, as the lifetime and the stability of conventional SPME fibers cannot meet the demands of analyzing relatively non-volatile compounds with more polar moieties. There have been attempts to analyze less volatile compounds by increasing the thermal, physical and chemical stability of the fibers. In this review, we present some new developments in the use of sol-gel technology, molecularly-imprinted polymers (MIPs) and electrochemical deposition to prepare thermally-stable, chemically-bonded, unbreakable SPME fibers.

A variety of novel triazolophthalazine derivatives is synthesized using 3-oxopropenyltriazolophthalazinones (III) as key intermediates.