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The reaction between configurably stable α-lithiated oxiranes and 3-substituted cyclobutanones allows obtaining enantiomerically enriched cyclobutanols (er > 98 : 2). These adducts, subjected to base-mediated Payne rearrangement, lead to the synthesis of a new class of oxaspirohexanes, useful precursors of 2,4-disubstituted cyclopentanones.

Recently, N-substituted anilines have been the object of increasing research interest in the field of organic chemistry due to their role as key intermediates for the synthesis of important compounds such as polymers, dyes, drugs, agrochemicals and pharmaceutical products. Among the various methods reported in literature for the formation of C–N bonds to access secondary anilines, the one-pot reductive amination of aldehydes with nitroarenes is the most interesting procedure, because it allows to obtain diverse N-substituted aryl amines by simple reduction of nitro compounds followed by condensation with aldehydes and subsequent reduction of the imine intermediates. These kinds of tandem reactions are generally catalyzed by transition metal-based catalysts, mainly potentially reusable metal nanoparticles. The rapid growth in the last years in the field of metal-based heterogeneous catalysts for the one-pot reductive amination of aldehydes with nitroarenes demands for a review on the state of the art with a special emphasis on the different kinds of metals used as catalysts and their recyclability features.

The regioselective functionalization of four- and six-membered cyclic sulfones was investigated using a lithiation/electrophile trapping strategy. The protocol features an interesting eco-compatibility profile because of the use of 2-MeTHF as a solvent (more eco-friendly than other organic solvents) and n-hexyllithium as a lithiating agent safer than other alkyllithium compounds. Several derivatives were prepared with different stereochemistry and substitution patterns. A number of selected derivatives, spanning a range of 5 log P units, were characterized for their lipophilicity through RP-HPLC. A good linear correlation, with a slope close to 1.0, was observed between the experimentally determined RP-HPLC lipophilicity parameters (log k'w) and calculated log P (clog P) values, whereas a systematic difference in absolute values between the chromatographic parameters and in silico lipophilicity descriptors can be attributed mainly to silanophilic interactions between the H-bond acceptor SO2 group and free silanol groups on silica-based C18 columns, which results in increased retention times.

An insight into the nano- and micro-structural morphology of a polymer supported Pd catalyst employed in different catalytic reactions under green conditions is reported. The pre-catalyst was obtained by copolymerization of the metal-containing monomer Pd(AAEMA)2 [AAEMA− = deprotonated form of 2-(acetoacetoxy) ethyl methacrylate] with ethyl methacrylate as co-monomer, and ethylene glycol dimethacrylate as cross-linker. This material was used in water for the Suzuki-Miyaura cross-coupling of aryl bromides, and for the reduction of nitroarenes and quinolines using NaBH4 or H2, as reductants. TEM analyses showed that in all cases the pristine Pd(II) species were reduced in situ to Pd(0), which formed metal nanoparticles (NPs, the real active species). The dependence of their average size (2–10 nm) and morphology on different parameters (temperature, reducing agent, presence of a phase transfer agent) is discussed. TEM and micro-IR analyses showed that the polymeric support retained its porosity and stability for several catalytic cycles in all reactions and Pd NPs did not aggregate after reuse. The metal nanoparticle distribution throughout the polymer matrix after several recycles provided precious information about the catalytic mechanism, which was truly heterogeneous in the hydrogenation reactions and of the so-called “release and catch” type in the Suzuki coupling.

The Apulia region in Italy has the longest Adriatic coastline; thus, maritime tourism is the driving force for its economic development. Pollution risk for four representative touristic ports of the region was assessed by determining the concentrations of 10 metals, 16 polycyclic aromatic hydrocarbons (PAHs) congeners, and the main nutrients. The cumulative mean Effects Range–Median quotient (mERMq) was used to assess the hazard degree, while the distribution patterns and content ratios of different PAH sediment concentrations were investigated to identify the pollution sources. Principal component analyses indicated an anomalous pollution trend for one of the small touristic ports assessed; this trend emerged from contamination by heavy metals and PAHs to a larger extent than expected, considering the main activity in this port, especially in its inner basin. The reason of this anomaly is thought to be the hydrodynamic and/or other stress factors.

By employing silver salts with a weakly coordinating anion Ag[A] ([A]=[FAl{OC12F15}(3)], [Al{OC(CF3)(3)}(4)]), two phosphaalkynes could be coordinated side-on to a bare silver-(I) center to form the unprecedented homoleptic complexes [Ag(eta(2)-P equivalent to CtBu)(2)][FAl{OC12F15}(3)] (1) and [Ag(eta(2)-P equivalent to CtBu)(2)]-[Al{OC(CF3)(3)}(4)] (2). DFT calculations show that the perpendicular arrangement in 1 is the minimum energy structure of the coordination of the two phosphaalkynes to a silver atom, whereas for 2 a unique square-planar coordination mode of the phosphaalkynes at Ag+ was found. Reactions with donor molecules yield the trigonally planar coordinated silver salts [((CH3)(2)CO) Ag(eta(2)-P equivalent to CtBu)(2)][FAl{OC12F15}(3)] (3) and [(C7H8)(2)Ag(eta(2)-P equivalent to CtBu)][FAl{OC12F15}(3)] (4). All of the compounds were comprehensively characterized in solution and in the solid state.

Background The mammalian bombesin receptor family comprises three G proteincoupled receptors: the neuromedin B receptor, the gastrin-releasing peptide receptor (BB2), and the bombesin receptor subtype 3. BB2 receptor plays a role in gastrointestinal functions; however, at present the role of this subtype in physiological and pathological conditions is unknown due to the lack of specific binders for all subclasses of bombesin receptors. Results Here, we present a study focused on the properties of the peptoid bombesin antagonist called PD176252, and other structural analogues with the aim to elucidate causes of their different affinity towards the BB2 receptor. Conclusion By means of computational techniques, based on QSAR, docking and homology building, supported by experimental data (X-ray diffraction and NMR spectroscopy) fresh insights on binding modes of this class of biological targets were achieved.

Platinum complexes bearing phosphane ligands in cis configuration with deprotonated flavonoids (3-hydroxyflavone, quercetin) and deprotonated ethyl gallate were synthesized starting from cis-[PtCl2(PPh3)(2)]. In all cases, O,O' chelate structures were obtained. While quercetin and ethyl gallate complexes are quite stable in solution, the 3-hydroxyflavonate complex undergoes a slow aerobic photodegradation in solution with formation of salicylic and benzoic acids. The X-ray diffraction structures of quercetin and ethyl gallate complexes are reported. Cell cycle studies (in the dark) of the complexes in two human cell lines revealed that the cytotoxic activity of the complex bearing 3-hydroxyflavonate is higher than those exhibited by 3-hydroxyflavone or by cis[PtCl2(PPh3)2] alone. Density functional theory studies on the hydrolysis pathway for the 3-hydroxyflavone and ethyl gallate complexes explained the different cytotoxic activity observed for the two compounds on the basis of the different intermediates formed during hydrolysis (relatively inert hydroxy Pt complexes for ethyl gal late and monoaqua complexes for 3-hydroxyflavone). (C) 2016 Elsevier Inc All rights reserved.

A simple and fast microwave-assisted hydrothermal method is proposed for the synthesis of magnetite nanoparticles. The addition of different surfactants (polyvinylpyrrolidone, oleic acid, or trisodium citrate) was studied to investigate the effect on size distribution, morphology, and functionalization of the magnetite nanoparticles. Microwave irradiation at 150 °C for 2 h of aqueous ferrous chloride and hydrazine without additives resulted in hexagonal magnetite nanoplatelets with a facet-to-facet distance of 116 nm and a thickness of 40 nm having a saturation magnetization of ~65 Am2 kg−1. The use of polyvinylpyrrolidone led to hexagonal nanoparticles with a facet-to-facet distance of 120 nm and a thickness of 53 nm with a saturation magnetization of ~54 Am2 kg−1. Additives such as oleic acid and trisodium citrate yielded quasi-spherical nanoparticles of 25 nm in size with a saturation magnetization of ~70 Am2 kg−1 and spheroidal nanoparticles of 60 nm in size with a saturation magnetization up to ~82 Am2 kg−1, respectively. A kinetic control of the crystal growth is believed to be responsible for the hexagonal habit of the nanoparticles obtained without additive. Conversely, a thermodynamic control of the crystal growth, leading to spheroidal nanoparticles, seems to occur when additives which strongly interact with the nanoparticle surface are used. A thorough characterization of the materials was performed. Magnetic properties were investigated by Superconducting Quantum Interference Device and Vibrating Sample magnetometers. Based on the observed magnetic properties, the magnetite obtained using citrate appears to be a promising support for magnetically transportable catalysts.

The carbonylation of the solvento species [(PHCy2)(L)Pt(-PCy2)(-H)Pt(PHCy2){P-P(OH)Cy-2}][BF4](2)(Pt-Pt) ([1-L](2+), L = CH2Cl2, thf, CH3CN) led to the formation of a singly bridged dicarbonyl Pt-I compound syn-[(PHCy2)(CO)Pt(-PCy2)Pt{P-P(OH)Cy-2}(CO)](+)(Pt-Pt) (2(+)). The reaction proceeded in two steps: 1) Substitution of L by CO to give the intermediate syn-[(PHCy2)(CO)Pt(-PCy2)(-H)Pt(PHCy2){P-P(OH)Cy-2}](2+)(Pt-Pt) ([1-CO](2+)) and 2) uptake of a second molecule of CO and elimination of [PH2Cy2](+) (as the BF4- salt) to give 2(+). The dicarbonyl complex [2][BF4] was also synthesized starting from the dicyclohexylphosphanido-bridged complex [(PHCy2)Pt(-PCy2){P-2,O--P(O)Cy-2}Pt(PHCy2)](Pt-Pt) (5). In this case the first step consisted of the carbonylation of 5 to give [(PHCy2)(2)Pt(-PCy2)Pt{P-P(O)Cy-2}(CO)](Pt-Pt) (6), which was transformed into 2(+) by protonation with HBF4 under an atmosphere of CO. Prolonged reaction times for the carbonylation of [1-L](2+) in halogenated solvents resulted in the formation of the symmetrical dicarbonyl compound syn-[(CO)(PHCy2)Pt(-PCy2)Pt(PHCy2)(CO)](+)(Pt-Pt) (3(+)) along with Cy2P(H)OBF3. Complexes 6 and [1-L][BF4](2) were also formed by the carbonylation of 5 and [1-OMe2][BF4](2) in the solid state.

The guarantee of the origin and quality of raw material is essential for the protection and valorization of Campana buffalo mozzarella cheese. The risk of utilization of semifinished products and stored milk in substitution for fresh milk is increasing, due to the continuous desire to reduce production costs. A proteomics approach and electrophoresis survey of retail mozzarella cheeses indicated different rates of proteolysis in the production of dairy industries. The use of fresh milk and correct cheesemaking protocol yielded only γ-caseins, which are derived from β-casein by plasmin, and para-κ-casein, which is derived from κ-casein by chymosin. The detection of abnormal hydrolysis resulting in β- and αS1-casein fragments, identified by mass spectrometry, indicates the use of stored milk or stored and pressed curd, or the reuse of unsold mozzarella cheese, to produce mozzarella. The formation of γ-caseins and other fragments during a long storage of raw materials at room or refrigeration temperature was ascribed to plasmin (endogenous milk enzyme), whereas formation of αS1-casein fragments, mainly αS1-I(6P)- and αS1-I(7P)-casein during the storage of curd was ascribed to the action of chymosin (exogenous enzyme) from rennet. Sodium dodecyl sulfate-PAGE and alkaline urea-PAGE permitted us to evaluate the freshness of the raw materials used in the manufacturing of buffalo mozzarella cheese and to reveal possible inappropriate preservation.

The oxidation of benzylic and secondary alcohols under homogeneous conditions was achieved at 40°C using molecular oxygen as the oxidant in the presence of excess 2-methylpropanal and catalytic amount of Co(acac)2. The oxidation reactions were also carried out with a heterogeneous analogue of Co(acac)2 revealing that the supported cobalt polymer acts as an active and reusable catalyst.

The reactions of [(cod)RhCl] 2 (cod=1,5-cyclooctadiene) and Na 2 PdCl 4 with the anion of 2-(acetoacetoxy)ethyl methacrylate (AAEMA − ) afforded (cod)Rh(AAEMA) ( 1 ) and Pd(AAEMA) 2 ( 2 ). Thermal copolymerization of 1 and 2 with suitable comonomers and cross-linkers yielded insoluble resins that have been characterised by elemental analyses, IR, UV–Vis, XPS and SEM techniques and successfully used in the hydrogenation of 1-heptene under mild conditions.

In this study, non-targeted H-1 NMR fingerprinting was used in combination with multivariate statistical techniques for the classification of Italian sweet cherries based on their different geographical origins (Emilia Romagna and Puglia). As classification techniques, Soft Independent Modelling of Class Analogy (SIMCA), Partial Least Squares Discriminant Analysis (PLS-DA), and Linear Discriminant Analysis (LDA) were carried out and the results were compared. For LDA, before performing a refined selection of the number/combination of variables, two different strategies for a preliminary reduction of the variable number were tested. The best average recognition and CV prediction abilities (both 100.0%) were obtained for all the LDA models, although PLS-DA also showed remarkable performances (94.6%). All the statistical models were validated by observing the prediction abilities with respect to an external set of cherry samples. The best result (94.9%) was obtained with LDA by performing a best subset selection procedure on a set of 30 principal components previously selected by a stepwise decorrelation. The metabolites that mostly contributed to the classification performances of such LDA model, were found to be malate, glucose, fructose, glutamine and succinate. (C) 2013 Elsevier Ltd. All rights reserved.

This study reports oil the first monodispersed molecular materials embodying the dibenzothiophene-5,5-dioxide core for the achievement of blue electroluminescence. The core has been functionalised in its 2.8- or 3,7-positions with dimethyl-fluorene (2,8-DBTOF and 3,7-DBTOF) or methyl-carbazole (2,8-DBTOC and 3,7-DBTOC) groups. The obtained compounds were characterised by (1)H and (13)C NMR, APCI-MS, thermal analysis (TGA and DSQ and cyclic voltammetry. Their optical and photophysical properties were investigated by UV and PL measurements as well as by time-dependent density-functional theory calculations. The materials were successfully employed as active layers ill blue to purplish blue p-i-n OLED devices. that reached, in the case of 3,7-DBTOC, performances as high as 11 422 cd m(-2) and 3.25 cd A(-1).

The reaction between Ni(0) complexes (dp) (dp = 1,2-bis(dicyclohexylphosphino)ethane, 1,3-bis(dicyclohexylphosphino)propane, 1,4-bis(dicyclohexylphosphino)butane; dcpe, dcpp, dcpb, respectively) and carbon dioxide is described. The influence of the PNiP bond angle on the stability of the corresponding adducts is discussed. The reactions of Ni(dcpp)CO2 and Ni(dcpb)CO2 with dioxygen are also described.

A novel bottom-gate top-contact OTFT architecture has been fabricated. In this device, a lipid bilayer structure embedding a photosynthetic membrane protein extracted from Rhodobacter Sphaeroides has been deposited onto the organic semiconductor film (α,ω-dihexylsexythiophene) prior to the evaporation of source and drain gold contacts. The figures of merit of this device were extracted and compared to those obtained for the same OTFT devoid of the biological film. Only slightly lower performances in terms of field-effect mobility (µ) were observed for the lipid bilayer OTFT that exhibits µ=0.007 cm2/Vs. This result constitutes a preliminary important starting point towards the development of novel highly sensitive and selective herbicides sensors.

The properties of a series of sexithiophenes bearing amide or ester functionalities in the alpha,omega-positions are reported. Isolation of the ester functionalities from the sexithiophene core by an ethylene spacer led to a device with moderate hole mobilities (1.2-10-2 cm2V-1s-1) and on/off ratios (103). A bottom contact device based on this sexithiophene showed a good response to a 5 ppm NO atmosphere, encouraging future studies on gas sensing OTFT based on these polar-functionalised OTFT.

Spin-coated films of 29H,31H-tetra-4-(2,4-di- tert -amylphenoxy)phthalocyanine (H 2 Pc) and [κ P ,μ-κ S -(dppeS)Pt(CH 3 )] 2 [BF 4 ] 2 have been used as sensing layers deposited in thin film form for the detection of VOCs. The sensing behaviour of the blend was predicted on the basis of mass spectrometric determinations performed on H 2 Pc/Pt-complex solutions, by monitoring the formation of gas-phase ions at the electrospray interface. The addition of small amounts of acetonitrile produced a [ M + 41] + peak whereas the addition of similar amounts of methanol, ethanol and isopropyl alcohol did not give the corresponding [ M + ROH] + species. These results were confirmed by sensing tests. A pure phthalocyanine optosensing element did not show relevant selectivity. Conversely, the heterogeneous sensing layer obtained by spin-coating deposition of a Pt-complex/H 2 Pc blend allowed the sensing of acetonitrile vapours with respect to the above mentioned alcohols.

The synthesis and characterization of poly(monofluorenylacetylenes) obtained by polymerization of 2-ethynyl-9,9-bis[(S)-3,7-dimethyl-octyl]fluorene and 2-ethynyl-9,9-bis[(S)-2-methylbutyl]fluorene are described. The effect of the structure of the alkyl chain at the C(9) position of fluorene on the properties of the materials was studied by differential scanning calorimetry, thermogravimetric analysis, X-ray diffraction analysis, UV/Vis spectroscopy, photoluminescence, and circular dichroism. Polymerization of chiral 2-ethynylterfluorene functionalized with (S)-2-methylbutylalkyl chains was studied. The resulting polymer exhibits high thermal stability; its emission spectrum occurs in the violet-blue region and shows no significant red shift on passing from a solution to the solid state.

The aerobic oxidation of substituted phenols with the catalytic system M(acac)n/3-methylbutanal/O2 has been investigated. Co(acac)2 and Mn(acac)3 promoted the transformation of 2,6-dimethylphenol and 2,6-di-t-butylphenol into their corresponding diphenoquinones and benzoquinones. In the oxidation of 2,3,6-trimethylphenol, the same catalysts yielded 32–34% of the relevant biphenol. Cu(acac)2 converted 2-naphthol into 1,1′-bi-2-naphthol with 84% yield. Supported Co(II) and Cu(II) complexes have also been used as heterogeneous catalysts for the oxidation of 2,6-di-t-butylphenol and 2-naphthol, respectively.

The catalytic activity of the cross-linked polymer obtained by reaction of Rh(cod)(AAEMA) [AAEMA − =deprotonated form of 2-(acetoacetoxy)ethyl methacrylate] and suitable acrylamides as comonomers and cross-linkers was investigated in the hydrogenation reactions of substrates such as olefins, unsaturated aldehydes and ketones, nitrobenzene and nitriles.

The initiation of the Suzuki cross-coupling polymerisation with a fluorene-based AB-type monomer was finely tuned within the chain-growth regime by the suitable control of the species generated by the Pd(AcO)2/t-Bu3P/K3PO4 catalytic system. The prototypical poly(9,9-di-n-octyl-fluorene) was obtained with extremely fast (1 min) polymerisation rates, excellent polydispersities (1.16) and molecular weights dependent on the monomer/catalyst molar ratio, without the need to resort to formal chain-initiators.

Reaction of [Ni(L–L)Cl2][L–L = Ph2P(CH2)nPPh2, n= 2(dppe) or 3 (dppp)] with NaOR (R = Me, Et or Pri) under a dinitrogen atmosphere afforded [Ni(L–L)2], Ni(OR)2 and aldehyde (or acetone when R = Pri) in 1 :1 :1 ratio, showing the peculiar reducing effect of alkoxide promoted by the chelating property of the phosphorus ligand. The reaction of NaOMe with [Ni(dcpe)Cl2][dcpe = 1,2-bis(dicyclohexylphosphino)-ethane] afforded mainly [Ni2(dcpe)3] when carried out in the absence of free diphosphine, and [Ni(dcpe)2] in the presence of free diphosphine. The reaction always yields the nickel(0) species [Ni(L–L)(CO)2] when it is carried out under a carbon monoxide atmosphere. The intermediate formation of unstable alkoxo(diphosphine)nickel(II) complexes has been demonstrated by recording the 31P NMR spectra of the reacting solutions at low temperature; in the case of the reaction of [Ni(dcpe)Cl2] with NaOMe only, it was possible to isolate as a solid the [Ni(dcpe)(OMe)2] complex, which has been fully characterized by analytical and spectroscopic (IR and 1H, 31P NMR) methods. A possible route by which nickel(0) complexes could be formed is discussed.

The synthesis and characterization of new complexes of formula Ni(dp), Ni(dp)C 7 H 8 (dp = 1,2-bis(dicyclohexylphosphino)ethane [dcpe]; 1,3-bis(dicyclohexylphosphino)propane [dcpp]; 1,4-bis(dicyclohexylphosphino)butane [dcpb]),Ni 2 (dcpe) 3 , Ni 2 (dcpb) 3 , Ni(depe) 2 and Ni(depe) 2 (depe = 1,2-bis(diethylphosphino)ethane) are described. The electronic spectra of these complexes are discussed.

The catalytic activity of some nickel-complexes in the dioxygen-induced carbonylation of amines has been studied. N,N′-oxamides expected on the basis of a previous report. The study of the reaction mechanism shows that amines are carbonylated in a reductive step, during which either ureas or oxamides can be obtained depending on the amount of water present. When dioxygen is used as the oxidant the oxidative step produces water, which promotes the urea formation. The oxygen is also responsible for the low yields owing to a side reaction involving amine oxidation. These conclusions were confirmed when the carbonylations were carried out under pseudo-catalysis conditions, or when oxidants which do not produce water in the oxidative step were used.

Nuclear Magnetic Resonance (NMR) methodologies offer a comprehensive characterization of foodstuff owing to the possibility to study a sample from different points of view including structural, compositional, functional, morphological etc. aspects. High resolution NMR spectroscopy applied to semi-solid food samples or to extracts in solution is used to determine the foodstuff composition. Here, some features of high resolution NMR methodologies related to food analysis such as quantitative analysis, chemometrics, and use of databases are included. Other NMR methodologies such as relaxometry and imaging described in this chapter give precious information regarding the morphology and texture of intact food samples.

The epoxidation of linear and cyclic olefins was catalysed by iron(III), nickel(II) and cobalt(II) centres immobilized on insoluble polymers. The latter were obtained by reaction of the polymerizable complexes of Fe(III), Ni(II) and Co(II) with 2-(acetoacetoxy)ethyl methacrylate with acrylamides.

The addition of β-dioxygenato compounds to methyl vinyl ketone was catalysed by nickel (II) and cobalt (II) complexes with the polymerizable β-ketoesterato 2-(acetoacetoxy)ethyl methacrylate (AAEMA − ) under homogeneous and heterogeneous phases. The homogeneous reactions were carried out using the soluble Ni(AAEMA) 2 and Co(AAEMA) 2 complexes whereas the heterogeneous catalytic tests were carried out using the copolymers obtained by reaction of M(AAEMA) 2 (M  Ni or Co) with suitable acrylamides.