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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.

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.

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.

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 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.

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.

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.

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.