A boronic analogue of the archetype matrix a-cyano-4-hydroxycinnamic acid (CHCA) has been synthesised providing a new ‘‘reactive matrix’’ that possesses molecular recognition properties. This matrix selectively recognizes vic-diols, a-hydroxyacids, aminols and first allowed the detection of anions as fluoride (unaffordable by usual matrices).

A systematic study on copper(II) as catalyst for the synthesis of glycerol carbonate via oxidative carbonylation is here reported for the first time. Copper(II) chloride has been found to efficiently promote the process under homogeneous conditions treating glycerol with CO:O2 (Ptot = 4 MPa; P(O2) = 0.7 MPa), in DMA at 130 ◦C and in the presence of pyridine as co-catalyst. Excellent conversions (>92%) and selectivities (>93%) are obtained in relatively short reaction times (3–4 h) also with copper(II) complexes. The catalyst overall TON is evaluated and new experimental evidences are provided allowing significant advancements in the mechanism comprehension.

Gold (Au) nanoparticles stabilized on metal oxide supports offer superior catalytic activity and recyclability in organic catalysis. We report for the first time synthesis of indium oxide stabilized gold (Au@In2O 3) nanocatalysts using an electrochemical procedure and their application in homocoupling of arylboronic acids. In2O3 nanoparticles prepared via sol-gel process are subjected to sacrificial anode electrolysis (SAE) under inert condition for electrodeposition of nano Au on In2O3. Thus Au@In2O3 nanoparticles obtained are thermally annealed at high temperature to partially oxidize Au and to remove any surfactants. XPS results show the existence of both elemental (nano Au0) and cationic (Au3+) species in Au@In 2O3 nanocatalysts, while SEM images confirm the presence of nanoscale Au (<10 nm) particles on In2O3 surface. Au@In2O3 nanocatalysts are tested for arylboronic acids homocoupling under different conditions and it is found that they are highly active in organic medium with K2CO3 base and demonstrate excellent conversion (>97%) and selectivity (>98%). The catalyst recyclability and performance towards differently substituted arylboronic acids is also studied and a plausible mechanism of action is proposed.

The present work is aimed at developing gold nanostructures functionalized with antenna systems to exploit the synergistic nanostructure/antenna desorption-ionization efficiency. A potential Matrix- Assisted Laser Desorption Ionisation (MALDI) organic matrix has been modified introducing specific functional groups or molecular linker and used as a capping agent for gold nanostructures. In particular, conjugated naphthyl-thio-derivative, i.e. 4-mercaptonaphthalene-1,8-dicarboxylic acid, was synthesized and characterized by means of nuclear magnetic resonance, UVevisible and X-ray photoelectron spectroscopies. Afterwards, the thio-derivative was used as covalent surface modifier for flat gold surfaces and nanostructured gold films. These surfaces were thoroughly characterized by means of parallel angle-resolved X-ray photoelectron spectroscopy to obtain quantitative information about elemental composition, chemical speciation, and in-depth distribution of the target chemical functional groups. Finally the compound was preliminarily tested as a non-conventional matrix in Laser Desorption Ionisation Mass Spectrometry (LDI-MS) analysis of low molecular weight biomolecules in order to assess its capability of acting as the antenna system and proton donor after covalent bonding to gold nanomaterials.

Low pressure plasma was used for preparing heterogeneous organocatalysts 2-(A)-(C) suitable for dioxirane-mediated epoxidations. Heterogenization was accomplished by adsorption of the methyl perfluoroheptyl ketone (2) on fluorinated supports (A)-(C) deriving from the treatment of commercial C₈-silica gel in low pressure plasma fed with fluorocarbons. Catalyst 2-(C) proved to be the most efficient one, promoting epoxidation of an array of alkenes, including unsaturated fatty esters like methyl oleate (10) and the triglyceride soybean oil (11), with the cheap potassium peroxymonosulfate KHSO₅ (caroate) as a green oxidant. Notably, the perfluorinated matrix gives rise to the activation of caroate, generating singlet oxygen. Materials were characterized by infrared Attenuated Total Reflectance spectroscopy (ATR-FTIR), X-ray Photoelectron Spectroscopy (XPS ) and Emission Scanning Electron Microscope (FESEM).

This chapter surveys the most significant developments in the field of palladium-catalyzed cross-coupling reactions in ionic liquids. The beneficial effect of the ionic liquids in terms of activity, selectivity, and recyclability is commented for all types of reactions discussed, namely the Heck, Suzuki–Miyaura, Stille, Sonogashira, Ullmann, and Negishi cross-couplings. Insights into the reaction mechanisms reveal that the effect of the ionic liquid on C–C bond forming reactions manifests itself not only in the energy lowering of polar transition states (or intermediates) involved in the catalytic cycles but also, depending on the cases, in the stabilization of palladium nanoparticles, the synthesis of molecular Pd complexes with the IL anions, the enhancement of the chemical reactivity of reactants, and others. The synergistic effect found by using appropriate mixtures of ionic liquids is also discussed. © Springer-Verlag Berlin Heidelberg 2013.

A simple method based on hydrophilic liquid chromatography (HILIC) and electrospray mass spectrometry (ESI-MS) for the detection of monoethanolamine (MEA) degradation products in CO2 post-combustion capture plants has been developed. MEA by-products determination has traditionally been difficult due to analytical separation problems. Even in recent sophisticated methods, this difficulty remains as the major issue often resulting in time-consuming sample preparations. In this work, we have collected samples directly from a real pilot plant and analyzed them, for the first time, by using matrix assisted laser desorption ionization (MALDI)-MS or ESIMS without any separation, both in positive and negative ionization modes. Alternatively, a previous liquid chromatography (LC) run was performed before ESI-MS; traditional reverse phase separation and HILIC were compared. Our results indicated that HILIC separation using an amino modified column, coupled to ESI-MS or ESI-MS/MS measurements, is the suitable method for identifying as many degradation products. Moreover, some plausible degradation mechanisms are proposed to explain some peaks in the spectra. The present work is intended as a preliminary study aiming to show the usefulness of these alternative techniques for this kind of investigations.

Bio-polyols synthesized from vegetables oils are a great alternative to petrochemical polyols for polyurethanes industry. The simplest approach to bio-polyols synthesis involves epoxidation of carbon –carbon double bond of unsaturated fatty ester moieties and subsequent epoxide ring-opening by nucleophilic reagents. In order to improve the latter process by increasing both productivity and product quality, the advantages of flow chemistry were exploited, such as facile automation, reproducibility, improved safety and process reliability, investigating for the first time in the literature the methanolysis reaction of epoxidized soybean oil (ESO) in a continuous flow mode. Compared with batch reaction, flow mode allowed the cut of the reaction time from 30 min to 2 min, and the reduction of catalyst concentration by an order of magnitude, which brought significant benefits in terms of cost efficiency and eco-sustainability, rendering the method suitable for industrial applications

The combined use of Pd(OAc)2, Cu(OAc)2, and dioxygen in molten tetrabutylammonium acetate (TBAA) promotes an unusual cyclopropanation reaction between aryl methyl ketones and styrenes. The process is a dehydrogenative cyclizing coupling that involves a twofold CH activation at the a-position of the ketone. The substrate scope highlights the flexibility of the catalyst; a reaction mechanism is also proposed.

Palladium nanoparticles have been electrochemically supported on zirconium oxide nanostructured powders and all the nanomaterials have been characterized by several analytical techniques. The Pd/ZrO2 nanocatalyst is demonstrated to be a very efficient catalyst in Heck, Ullmann, and Suzuki reactions of aryl halides in water. The catalyst efficiency is attributed to the stabilization of Pd nanophases provided by tetra(alkyl)- ammonium hydroxide, which behaves both as base and PTC (phase transfer catalyst) agent.

Palladium nanoparticles have been electrochemically supported on zirconium oxide nanostructured powders and all the nanomaterials have been characterized by several analytical techniques. The Pd/ZrO2 nanocatalyst is demonstrated to be a very efficient catalyst in Heck, Ullmann, and Suzuki reactions of aryl halides in water. The catalyst efficiency is attributed to the stabilization of Pd nanophases provided by tetra(alkyl)- ammonium hydroxide, which behaves both as base and PTC (phase transfer catalyst) agent.

An efficient N-selective alkylation of primary aromatic amines in molten quaternary ammonium salts, as the solvent, under relatively mild and base-free conditions is presented. On the basis of the Kamlet–Taft parameters and the nucleophilicity of the IL (ionic liquid) anions, the influence of the ionic liquid was evaluated. This protocol was validated on a larger multigram scale and with the syntheses of bioactive heterocycles (e.g., 1,4-benzothiazine and quinoxalines) and new efficient MALDI matrixes.

Catalysis by transition-metal nanoparticles has undergone an explosive growth during the past decade. This special issue presents the general trends in the current research in this field, the present situation concerning scope and limitations, as well as the future perspectives. Original contributions are also presented on the applications of nano-catalysts to the green synthesis.

Palladium nanoparticles supported on chitosan (Pd-NPs@Chitosan) have been used for the first time in Suzuki cross coupling of bromo and iodoarenes carried out in ionic liquids. The reaction proceeded smoothly in molten tetrabutylammonium bromide (TBAB) affording unsymmetrical biaryls in good to excellent yields. A low catalyst loading (0.1%) is used and the catalyst can be recycled without deactivation.