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Projects: (i)FIRB-MIUR "Simulazione dei flussi lavici con gli automi cellulari" N. RBAU01RMZ4_002, (ii) “Sviluppo di sistemi di monitoraggio’ funded by Dipartimento di Protezione Civile della Regione Sicilia, INGV (Istituto Nazionale di Geofisica e Vulcanologia, sezione di catania - Italy), (iii) EU-funded Sixth Framework Programme project 18354 “NOVAC, (iv)Leverhulme Trust fellowship.

A novel two-step synthesis of 2-hydroxymethylbenzofurans 3 and 2-alkoxymethylbenzofurans 4-6, based on palladium-catalyzed cycloisomerization of 2-(1-hydroxyprop-2-ynyl)phenols 1 under basic conditions to give 2-methylene-2,3-dihydrobenzofuran-3-ols 2, followed by acid-catalyzed isomerization or allylic nucleophilic substitution with alcohols as nucleophiles, is reported. Cycloisomerization reactions leading to 2 (80-98% yields) were carried out at 40 degrees C in MeOH as the solvent, in the presence of a base and catalytic amounts of PdX2 + 2KX (X = Cl, I). Isomerization reactions of 2 readily occurred at 25-60 degrees C in DME as the solvent, with H2SO4 as the proton source, to give 2-hydroxymethylbenzofurans 3 in 65-90% yields. In a similar manner, allylic nucleophilic substitution reactions of 2 with ROH as nucleophiles [carried out at 25-40 degrees C in ROH (R = Me) or ROH-DME mixtures (R = Bu, Bn) in the presence of H2SO4] afforded 2-alkoxymethylbenzofurans 4, 5, and 6 (R = Me, Bu, and Bn, respectively), in 65-98% yields.

A novel approach to coumarin derivatives has been developed starting from readily available 2-(1-hydroxyprop-2-ynyl)phenols, based on an unprecedented palladium-catalyzed dicarbonylation process. Reactions were carried out in the presence of catalytic amounts of PdI2 in conjunction with an excess of KI in MeOH as the solvent at room temperature and under 90 atm of CO to give 3-[(methoxycarbonyl)methyl]coumarins in good to high isolated yields (62-87%).

Alkynols undergo palladium-catalyzed aminocarbonylation leading to the direct formation of different heterocyclic derivatives, depending on the position of the OH group with respect to the triple bond. In the cases of 4-yn-1-ols and ( Z)-2-en-4-yn-1-ols, the initially formed 2-ynamide intermediates, respectively, undergo cyclization leading to tetrahydrofuran derivatives or 2-furan-2-ylacetamides, respectively. In the case of 2-yn-1-ols, the aminocarbonylation products undergo intermolecular conjugate addition, followed by lactonization, leading to aminofuranones.

A practical and efficient protocol has been developed to realize the catalytic rearrangement of allyl but-3-enoate to heptadienoic acids in NaHCO 3 saturated water, in the presence of catalytic amounts of a rhodium(I) complex, containing olefin, diene or phosphine ligands. The reaction mainly affords the sodium salt of E -2,6-heptadienoic acid, with high catalytic efficiency (3600 TON). A reaction scheme of the process is proposed. The reaction course differs from that observed in organic solvents, where E -3,6-heptadienoic acid is formed predominantly.

A general and convenient synthesis of substituted quinolines by regioselective copper- or palladium-catalyzed 6-endo-dig cyclization-dehydration of 1-(2-aminoaryl)-2-yn-1-ols is reported. The crude substrates were easily obtained by the Grignard reaction between the appropriate alkynylmagnesium bromide and 2-aminoaryl ketones and could be used without further purification for the subsequent cyclization step. Heteroannulation reactions were carried out in MeOH or DME as the solvent at 60 or 100 degrees C in the presence of CuCl(2) or PdX(2) (in conjunction with 10 equiv of KX, X = Cl, I) as the catalyst to afford the quinoline derivatives in good to excellent isolated yields based on starting 1-(2-aminoaryl)-2-yn-1-ols (66-90%).

New liquid crystalline stilbene derivatives containing 1,2-dienylalkoxy chains 1 (n = 7, 9, 11) have been synthesized and their mesomorphic properties have been measured by polarizing optical microscopy, differential scanning calorimetry, and absorption spectroscopy. The effect of terminal alkoxy chain length and polimerisable function on the mesomorphic behaviour is discussed.

A new kind of solid plastic electrochromic (EC) film, prepared by introducing EC molecules, belonging to a class of bipyridinium salts (viologens), and plasticizers into preformed solid thermoplastic polymers, is presented. The particularly easy preparation of this EC device makes it suitable for large-scale applications, by simple lamination of the film between conductive glasses. In this way it is possible to eliminate the disadvantages of fast EC films, due to the variation of the solvent organization around the EC molecules and to the onset of the hydrostatic pressure of the fluid layer which can break or separate from the glass supports. The electrochromic cells based on our solid films have undergone up to 105 operational cycles in which coloring, bleaching processes, and stationary state conditions have been adjusted by applying suitable electric pulse sequences.

Starting off from a review of previous literature on kinematic models of the unstable eastern flank of Mt. Etna, we propose a new model. The model is based on our analysis of a large quantity of multidisciplinary data deriving from an extensive and diverse network of INGV monitoring devices deployed along the slopes of the volcano. Our analysis had a twofold objective: first, investigating the origin of the recently observed slow-slip events on the eastern flank of Mt. Etna; and second, defining a general kinematic model for the instability of this area of the volcano. To this end, we investigated the 2008–2013 period using data collected from different geochemical, geodetic, and seismic networks, integrated with the tectonic and geologic features of the volcano and including the volcanic activity during the observation period. The complex correlations between the large quantities of multidisciplinary data have given us the opportunity to infer, as outlined in this work, that the fluids of volcanic origin and their interrelationship with aquifers, tectonic and morphological features play a dominant role in the large scale instability of the eastern flank of Mt. Etna. Furthermore, we suggest that changes in the strain distribution due to volcanic inflation/deflation cycles are closely connected to changes in shallow depth fluid circulation. Finally, we propose a general framework for both the short and long term modeling of the large flank displacements observed.

The oxidative carbonylation of readily available (Z)-(2-en-4-ynyl)amines, catalyzed by the PdI 2 -KI system, selectively afforded in satisfactory yields (40-95 %) either pyrrole-2-acetic ester or (pyridine-2-one)-3-acetic amide derivatives, depending on the susbtitution pattern of the substrate and the reaction conditions. The presence of an excess of carbon dioxide proved in most cases to be beneficial to both the reaction rate and product selectivity.

Polymer-dispersed liquid crystals (PDLCs) are liquid-crystal dispersions within a polymer matrix. These films can be changed from an opaque to a transparent state by applying a suitable alternating-current electric field. PDLCs have attracted the interest of researchers for their applications as light shutters, smart windows, and active displays. For such applications, electrochromic devices, which change color as a result of electrochemical reactions, have also become a recent focus of research. Herein, we report our preliminary results on bifunctional devices based on PDLCs that host electrochromic guest molecules. Such devices allow both an independent and fast switching from a scattering opaque state to a transmissive transparent state owing to liquid-crystal reorientation and a color change from white (pale yellow) to dark blue, due to either oxidation or reduction of the electrochromic molecules.

Some PdI 2 -based complexes have proved to be efficient catalysts for the selective, atom-economical synthesis of different important heterocyclic derivatives starting from very simple building blocks, such as simple or functionalized alkynes, amino alcohols, diamines, carbon monoxide, carbon dioxide, alcohols, water, and oxygen. The synthetic protocols leading to heterocycles have been grouped into three classes of reactions: (a) cycloisomerization of (Z)-2-en-4-yn-1-ols, (Z)-2-en-4-yne-1-thiols, (Z)-(2-en-4-ynyl)amines, 2-alkynylbenzyl alcohols to give substituted furans, thiophenes, pyrroles, and 1,3-dihydroisobenzofurans or 1H-iso-chromenes, respectively; (b) oxidative carbonylation of simple alkynes, 1,5-diynes, functionalized alkynes bearing a suitably placed nucleophilic group, amino alcohols, and diamines to afford substituted maleic anhydrides, functionalized p- and γ-lactones, β- and γ-lactams, dihydroindol-2-ones, furans, pyrroles, thiophenes, tetrahydrofurans, oxazolidin-2-ones, oxazolines, cyclic ureas, 4H-3,1-benzoxazines, quinazolin-2-ones, quinolin-4-ones; (c) reductive carbonylation of alkynes to give substituted γ-lactones and formation of lactone or anhydride derivatives by additive carbonylation, resulting from the combination between oxidative carbonylation of the triple bond and reduction of a suitable functional group present in the substrate itself.

A direct synthesis of 1-(alkoxycarbonyl)methylene-1,3-dihydroisobenzofurans 2 and 5 and 4-(alkoxycarbonyl)benzo[c]pyrans 3 and 6 by oxidative Pd-catalysed cyclization/alkoxycarbonylation of 2-alkynylbenzyl alcohols 1, and of 2-alkynylbenzaldehydes or 2-alkynylphenyl ketones 4 is reported. Reactions were carried out in ROH or CH3CN/ROH (R = Me, iPr) as the solvent at 70−105 °C in the presence of catalytic amounts of PdI2 in conjunction with KI under a 4:1 or 3:1 CO/air mixture (2.0 or 3.2 MPa total pressure at 25 °C). The reaction occurs through intramolecular attack by the nucleophilic oxygen atom (either already present in the starting material, as in 1, or generated in situ by ROH attack on carbonyl group, as in 4) on the triple bond coordinated to PdII, followed by alkoxycarbonylation. The presence of substituents at the alkyne terminal position and at the carbon atom α to the hydroxy group play a key role in the selectivity of the process towards the formation of a five- or six-membered ring. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

A novel synthesis of 4-dialkylamino-5H-furan-2-ones 3 starting from very simple building blocks, i.e., α-substituted 2-yn-1-ols 1, carbon monoxide, dialkylamines 2 and oxygen is reported. Reactions are carried out in 1,2-dimethoxyethane at 100 °C and under 20 atm (at 25 °C) of a 4/1 mixture of CO/air in the presence of catalytic amounts of PdI2 in conjunction with 10 equiv. of KI. Formation of 3 occurs through an ordered sequence of steps, namely (a) Pd-catalyzed oxidative monoaminocarbonylation of 1 to give 4-hydroxy-2-ynamides 4, which can be isolated under appropriate conditions; (b) stereoselective conjugate addition of 2 to the triple bond of 4, with formation of (not isolated) (E)-3-dialkylamino-4-hydroxy-2-enamides; (c) intramolecular alcoholysis of the amide function of the latter to give the final product 3.

Continuous monitoring of soil CO2 dynamic concentration (which is proportional to the CO2 flux through the soil) was carried out at a peripheral site of Mt. Etna during the period November 1997–September 2000 using an automated station. The acquired data were compared with SO2 flux from the summit craters measured two to three times a week during the same period. The high frequency of data acquisition with both methods allowed us to analyze in detail the time variations of both parameters. Anomalous high values of soil CO2 dynamic concentration always preceded periods of increased flux of plume SO2, and these in turn were followed by periods of summit eruptions. The variations were modeled in terms of gas efflux increase due to magma ascent to shallow depth and its consequent depressurization and degassing. This model is supported by data from other geophysical and volcanological parameters. The rates of increase both of soil CO2 dynamic concentration and of plume SO2 flux are interpreted to be positively correlated both to the velocity of magma ascent within the volcano and to lava effusion rate once magma is erupted at the surface. Low rates of the increase were recorded before the nine-month-long 1999 subterminal eruption. Higher rates of increase were observed before the violent summit eruption of September-November 1999, and the highest rates were observed during shorter and very frequent spike-like anomalies that preceded the sequence of short-lived but very violent summit eruptions that started in late January 2000 and continued until late June of the same year. Furthermore, the time interval between the peaks of CO2 and SO2 in a single sequence of gas anomalies is likely to be controlled by magma ascent velocity.

A novel approach to functionalized isoindolinone derivatives 3 is presented. It is based on a cascade process, consisting of PdI 2 /KI-catalyzed oxidative monoaminocarbonylation of secondary 2-ethynylbenzamides 1 with nucleophilic secondary amines 2 , followed by intramolecular conjugate addition of the arylamido group to the alkynylamido group of the intermediate alkynylamides. Products have been obtained in high to excellent yields starting from different N -alkyl 2-ethynylbenzamides and amines, under relatively mild conditions (100 °C under 40 atm of a 4:1 mixture of CO–air), working in a MeCN–amine mixture (2:1, v/v) for 5–15 h.

We have found that carbon dioxide effectively promotes the Pd-catalyzed oxidative carbonylation of terminal alkynes to give maleic anhydrides in fair yields. Reactions were carried out in aqueous dioxane at 60−80 °C in the presence of catalytic amounts of PdI2 in conjunction with KI and under a 4:1:10 mixture of CO/air/CO2 (60 atm total pressure at 25 °C). By working in the presence of a large excess of water, maleic acids were formed selectively with unprecedented catalytic efficiencies for this kind of reaction. In the latter case, the use of an excess of carbon dioxide tended to inhibit, rather than promote, the reaction. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

A variety of prop-2-ynylamides have been carbonylated under oxidative conditions to give oxazolines, oxazolines with chelating groups, and bisoxazolines bearing an (alkoxycarbonyl)methylene chain at the 5 position in good yields. The cyclization-alkoxycarbonylation process was carried out in alcoholic media at 50-70 degrees C and under 24 bar pressure of 3:1 carbon monoxide/air in the presence of catalytic amounts of 10% Pd/C or PdI2 in conjunction with KI. Cyclization occurred by anti attack of an oxygen function on the palladium-coordinated triple bond, followed by stereospecific alkoxycarbonylation, strictly resulting in E-stereochemistry. The structures of representative oxazolines and bisoxazolines have been determined by X-ray diffraction analysis.

Stromboli is known for its mild, persistent explosive activity from the vents located within the summit crater depression at the uppermost part of the Sciara del Fuoco (SdF) depression. Effusive activity (lava flows) at this volcano normally occurs every 5–15 years, involving often the opening of eruptive fissures along the SdF, and more rarely overflows from the summit crater. Between the end of the 2007 effusive eruption and December 2012, the number of lava flows inside and outside the crater depression has increased significantly, reaching a total of 28, with an average of 4.8 episodes per year. An open question is why this activity has become so frequent during the last 6 years and was quite rare before. In this paper, we describe this exceptional activity and propose an interpretation based on the structural state of the volcano, changed after the 2002–2003 and even more after the 2007 flank effusive eruption. We use images from the Stromboli fixed cameras network, as well as ground photos, plume SO2 and CO2 fluxes released by the summit crater, and continuous fumarole temperature recording, to unravel the interplay between magma supply, structural and morphology changes, and lava flow output. Our results might help forecast the future behaviour and hazard at Stromboli and might be applicable to other open-conduit volcanoes.

Mt. Etna volcano in Italy is one of the most active degassing volcanoes worldwide, emitting a mean of 1.7 Mt/year of Sulphur Dioxide (SO2) in quiescent periods. In this work, SO2 measurements retrieved by Moderate Resolution Imaging Spectroradiometer (MODIS), hyper-spectral Infrared Atmospheric Sounding Interferometer (IASI) and the second Global Ozone Monitoring Experiment (GOME-2) data are compared with the ground-based data from the FLux Automatic MEasurement monitoring network (FLAME). Among the eighteen lava fountain episodes occurring at Mt. Etna in 2011, the 10 April paroxysmal event has been selected as a case-study for the simultaneous observation of the SO2 cloud by satellite and ground-based sensors. For each data-set two retrieval techniques were adopted and the measurements of SO2 mass and flux with their respective uncertainty were obtained. With respect to the FLAME SO2 mass of 4.5 Gg, MODIS, IASI and GOME-2 differ by about 10%, 15% and 30%, respectively. The SO2 flux correlation coefficient between MODIS and FLAME is 0.84. All the retrievals within the respective errors are in agreement with the ground-based measurements supporting the validity of these space measurements.

A novel synthesis of 2-ynamides (3) by palladium-catalyzed oxidative aminocarbonylation of alk-1-ynes (1) is reported. Reactions are catalyzed by PdI2/KI and are carried out at 100°C in dioxane as the solvent in the presence of dialkylamines (2) as nucleophiles (amine/alk-1-yne molar ratio=1/1) using a 4/1 CO/air mixture (20 atm total pressure at 25°C).

A simple and economical synthesis of substituted furans and pyrroles, by ligand-free CuCl2-catalyzed heterocyclodehydration of readily available 3-yne-1,2-diols and N-Boc- or N-tosyl-1-amino-3-yn-2-ols, respectively, is presented. Reactions are carried out in MeOH at 80–100 °C for 1–24 h and afford the corresponding heterocyclic derivatives in 53–99% isolated yields.

A novel and convenient approach to furan-3-carboxylic esters 2 is presented, based on palladium-catalyzed direct oxidative carbonylation of readily available 3-yne-1,2-diols 1 . The process, corresponding to a sequential combination between a 5- endo - dig heterocyclodehydration step and an oxidative alkoxycarbonylation stage, is catalyzed by PdI 2 in conjunction with an excess of KI under relatively mild conditions (100 °C in ROH under 40 atm of a 4:1 mixture of CO-air).

4-Yn-1-ols bearing a terminal triple bond undergo oxidative cyclization–alkoxycarbonylation in methanol at 70°C and 100 atm of a 9:1 mixture of carbon monoxide and air in the presence of catalytic amounts of [PdI 4 ] 2− in conjunction with an excess of KI to give 2 E -[(methoxycarbonyl)methylene]tetrahydrofurans in good yields. A competing reaction, cycloisomerization–hydromethoxylation leading to 2-methoxy-2-methyltetrahydrofurans, can be easily curtailed by increasing the KI excess. The latter products can be prepared from 4-yn-1-ols and methanol in high yields using the same catalytic system and without KI excess in the absence of carbon monoxide.

In the presence of a PdI 2 -based catalytic system, 1,2-diols undergo an oxidative carbonylation process to afford 5-membered cyclic carbonates in good to excellent yields (84–94%) and with unprecedented catalytic efficiencies for this kind of reaction (up to ca. 190 mol of product per mol of PdI 2 ). Under similar conditions, 6-membered cyclic carbonates are obtained for the first time through a direct catalytic oxidative carbonylation of 1,3-diols (66–74% yields).

A variety of (Z)-2-en-4-yn-1-ols have been carbonylated under oxidative conditions to give substituted furan-2-acetic esters in good yields. The cyclization−alkoxycarbonylation process occurs in alcoholic media at 50−70 °C and under 100 atm pressure of a 9:1 mixture of carbon monoxide and air in the presence of catalytic amounts of PdI2 in conjunction with KI. The proposed reaction pathway involves the in situ isomerization of the initially formed (E)-2-[(alkoxycarbonyl)methylene]-2,5-dihydrofuran species, which in some cases have been isolated and shown to be the intermediates.

Conditions for the sequential reaction of carbon dioxide with an acetylenic amine and carbon monoxide in the presence of a PdI 2 –KI catalyst in alcohols are examined. The stereochemistry of the two 5-(alkoxycarbonyl)methylene-3,4,4-trialkyl-1,3-oxazolidin-2-one stereoisomers obtained is attributed to different pathways on the basis of experiments carried out on alkyl and benzyl esters of N -alkyldimethylpropynylcarbamic acid and carbon monoxide.

Furan-2-acetic esters are obtained in good yields by direct oxidative cyclization-alkoxycarbonylation of ( Z )-2-en-4-yn-1-ols, bearing both an alkyl or an aryl substituent α to the hydroxy group, in the presence of catalytic amounts of palladium iodide in conjunction with potassium iodide at 50–70°C and 100 atm of a 9:1 mixture of carbon monoxide and air.

The unprecedented eco-friendly Pt-catalyzed 5-endo-dig cycloisomerization of readily available α-amino ynones is reported under microwave irradiation in PEG-3400 as reaction matrix. The corresponding pure pyrrolin-4-ones were obtained in excellent yields (80–98%) directly after a straightforward precipitation–filtration workup, thus avoiding any chromatographic purification. The catalytic system was recycled and the chiral purity of all the products was also investigated.

The unprecedented electrophilic iodo-mediated cyclization of α-amino-ynones afforded enantiomerically enriched β-iodopyrrolin-4-ones in excellent yields under mild conditions. The starting substituted α-amino-ynones were obtained from the chiral pool by selective mono-addition of an organolithium to optically pure N-protected carboxyanhydrides of amino acids (UNCAs).

Recent advances in the field of oxidative carbonylation reactions leading to carbonylated heterocyclic derivatives are presented (coverage: 2006 to the beginning of 2012).

Quiescent and explosive magma degassing at Stromboli volcano sustains high-temperature crater gas venting and a permanent volcanic plume which constitute key sources of information on the magma supply and dynamics, the physical processes controlling the explosive activity and, more broadly, the volcano feeding system. The chemical composition and the mass output of these crater emissions (gases, trace metals, radioactive isotopes) were measured using different methodologies: within-plume airborne measurements, ground-based plume filtering, and/or in situ analysis, remote UV and open-path Fourier transform infrared absorption spectroscopy. The results obtained, summarized in this paper, demonstrate a primary control of the magmatic gas phase on the eruptive regime and the budget of the volcano. The large excess gas discharge, compared with the lava extrusion rate, and the source depth of slug-driven Strombolian explosions evidence extensive separate gas transfer across the volcano conduits, promoted by the high gas content (vesicularity) and then permeability of the shallow basaltic magma. Combined with data for volatiles dissolved in olivine-hosted melt inclusions, the results provide updated constraints for the magma supply rate (similar to 0.3 m(3) s(-1) average), the ratio of intrusive versus extrusive magma degassing (similar to 15), and the amount of unerupted degassed magma that should be convectively cycled back in conduits and accumulated beneath the volcano over time (similar to 0.25 km(3) in the last three decades). The results also provide insight into the possible triggering mechanism of intermittent paroxysmal explosions and the geochemical signals that might allow forecasting these events in the future.

The 2002-2003 effusive eruption of Stromboli volcano represents an excellent opportunity to investigate the transition from effusive to explosive activity at an open-conduit basaltic system, when activity migrated from effusive vents, at the base of the craters, to summit explosions. The transition is investigated here through the analysis of very long period seismicity, delay times between infrasonic and thermal onsets of explosions, and SO2 flux recorded during a 1-year period. The synergy of the multiple geophysical observations points to a magma-driven migration of the magma column. Here the increased magma supply at the eruption onset lead to opening of effusive fissures, which draining the magma in the shallow conduit caused the decrease of the magma level. The decrease of the magma supply at the end of the effusion lead to sealing of effusive fissures, upraise of the magma level within the conduit, and reestablishment of explosive activity from the summit vents.

A novel approach to functionalized isoindolinone derivatives 3 is presented. It is based on a cascade process, consisting of PdI 2 /KI-catalyzed oxidative monoaminocarbonylation of secondary 2-ethynylbenzamides 1 with nucleophilic secondary amines 2 , followed by intramolecular conjugate addition of the arylamido group to the alkynylamido group of the intermediate alkynylamides. Products have been obtained in high to excellent yields starting from different N -alkyl 2-ethynylbenzamides and amines, under relatively mild conditions (100 °C under 40 atm of a 4:1 mixture of CO–air), working in a MeCN–amine mixture (2:1, v/v) for 5–15 h.

The reaction provides a convenient, mild, and widely applicable method to prepare substituted thiophenes under either conditions A) or B).

Allyl alcohols can be efficiently carbonylated to β,γ-unsaturated acids or esters in dimethylacetamide (DMA) or MeOH DMA mixtures under relatively mild conditions (80°C, 50–100 atm) using a simple catalytic system consisting of palladium iodide in the presence of thiourea as ligand. In the case of but-2-ene-1,4-diol, selectivation to methyl 5-hydroxypent-3-enoate, 3,6-dihydro-1,2-pyrone or dimethyl hex-3-enedioate may be achieved.

The electrical properties of polymer-dispersed liquid crystals (PDLCs) are an important characteristic in their electro-optical performance. Conductivity effects can set up depolarization fields in the films reducing the effective field across the liquid crystal droplets. Both theoretical and experimental investigations have confirmed that the electric field across nematic droplets depends on the liquid crystal and polymer conductivities. In this letter, we have found that the doping of a PDLC with low percentages of a conductive polymer allows a fine adjustment of polymer matrix conductivity. In addition, we have found a large reduction in the re-orientation fields and relaxation times as a function of conductive polymer loading. Results are in rather good agreement with a simple phenomenological model.

A novel approach to 3-iodothiophenes by direct iodocyclization of alkynylthiol derivatives is presented. A variety of 1-mercapto-3-yn-2-ols 5 (readily available from alkynylation of the corresponding alpha-mercapto ketones or alpha-mercapto esters) were smoothly converted into the corresponding 3-iodothiophene derivatives 6 in good yields by reaction with molecular iodine in the presence of NaHCO3 at room temperature in MeCN as the solvent.

alfa-Methylene-beta-lactams possessing a Z-alkoxycarbonyl group are formed directly from the reaction of N-alkyl-substituted prop-2-ynylamines with CO, air and alcohols, under the catalytic action of palladium on carbon in conjunction with potassium iodide, while gamma-lactams or oxazolines are obtained with unsubstituted or acylated amines.

International audience; The unprecedented electrophilic iodo-mediated cyclization of α-amino-ynones afforded enantiomerically enriched β-iodopyrrolin-4-ones in excellent yields under mild conditions. The starting substituted α-amino-ynones were obtained from the chiral pool by selective mono-addition of an organolithium to optically pure N-protected carboxyanhydrides of amino acids (UNCAs).

A variety of readily available 1-mercapto-3-yn-2-ols 5 were conveniently converted into the corresponding thiophenes 6 in good to high yields in MeOH as the solvent at 50-100 °C in the presence of catalytic amounts (1-2%) of PdI(2) in conjunction with KI (KI:PdI(2) molar ratio = 10). The catalyst could be made recyclable employing an ionic liquid, such as BmimBF(4), as the solvent under suitable conditions.

Microwave-assisted iodocyclization of diols (I) or amino alcohols (III) is achieved in the presence of NaHCO3.

A new and convenient method to prepare a number of pyrrole-3-carboxylic esters is reported.

The necessity of understanding volcanic phenomena so as to assist hazard assessment and risk management, has led to development of a number of techniques for the tracking of volcanic events so as to support forecasting efforts. Since 1980s scientific community has progressively drifted research and surveillance at active volcanoes by integrated approach. Nowadays, volcano observatories over the world record and integrate real or near-real time data for monitoring and understanding volcano behaviour. Among the geophysical, geochemical, and volcanological parameters, the tracking of temperature changes at several volcanic features (e.g. open-vent systems, eruptive vents, fumaroles) and variations in sulphur dioxide flux and concentration at volcanic plumes are key factors for studying and monitoring active volcanoes.

Palladium-catalyzed oxidative heterocyclization—alkoxycarbonylation of in situ generated o-alkynylbenzylideneamines proceeds smoothly to afford isoquinoline derivatives (IV) in moderate yields.

Novel and convenient approaches to benzothiophene derivatives 3 and 5 have been developed, based on heterocyclization reactions of 1-(2-mercaptophenyl)-2-yn-1-ols 2 or 4, respectively, readily available from alkynylation of 2-mercaptobenzaldehydes or 1-(2-mercaptophenyl) ketones 1. In particular, 1-(2-mercaptophenyl)-2-yn-1-ols 2, bearing a CH2R substituent on the triple bond (R = alkyl, aryl), were conveniently converted in fair to good yields (55–82%) into (E)-2-(1-alkenyl)benzothiophenes 3 when allowed to react in the presence of catalytic amounts (2 mol %) of PdI2 in conjunction with KI (KI:PdI2 molar ratio =10) at 80–100 °C in MeCN as the solvent, through a heterocyclodehydration process. On the other hand, 2-alkoxymethylbenzothiophenes 5 were selectively obtained in fair to excellent yields (49–98%) via a radical-promoted substitutive heterocyclodehydration process, by reacting 1-(2-mercaptophenyl)-2-yn-1-ols 4 (bearing an alkyl or aryl substituent on the triple bond) in alcoholic media at 80–100 °C...

Thermal imagery obtained with portable infrared cameras is widely used to track and measure volcanic phenomena. In the case of explosive eruptions, both air and ground-based thermal monitoring have enabled collection of data streams from relatively safe distances. Analysis of these data have enabled the characterisation of different explosive regimes, parameterisation of eruptive plumes, and assessment on the dynamics occurring in the shallow system. Here we explore the suitability of infrared imagers for investigating the short time scale eruptive behaviour of three basaltic volcanoes. We present high-time resolution thermal image data-sets recorded at Etna, Stromboli and Kīlauea volcano. At the time of observations, all three exhibited pulsed degassing. Signal processing of the mean apparent temperature time-series highlights four broad classes of cyclic temperature changes at the three volcanoes based on characteristic time-scales revealed in the periodograms: (1)