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Despite the high relevance of 1,3-dienes, stereoselective methods to access tetrasubstituted conjugated dienes are still scarce. We here report an efficient and modular approach that provides access to multifunctional tetrasubstituted 1,3-dienes with excellent levels of regio- and stereoselectivity. This methodology is based on a tetracomponent reaction between a borylated dendralene, an organolithium reagent and two different electrophiles. Mechanistic studies reveal that this transformation proceeds through a regio- and stereoselective carbolithiation/electrophilic trapping of an in situ formed dendralenic boron-ate complex, followed by a stereoretentive halodeborylation. The ease in which complex structural dienes can be accessed and their synthetic versatility highlight the importance and utility of this method ; Financial support from the AEI (CTQ2017-88451-R), Xunta de Galicia (ED431C 2018/04; Centro singular de investigación de Galicia accreditation 2019–2022, ED431G 2019/03) and the European Union (European Regional Development Fund—ERDF) is gratefully acknowledged. E. R.-C. thanks Xunta de Galicia for a predoctoral fellowship ; SI

A copper-catalyzed protoboration of borylated dendralenes is reported. The method employs an NHC–Cu catalyst and provides access to 1,4-addition products with excellent levels of chemo-, regio- and stereoselectivity. The resulting diene bis(boronates) are oxidized to the corresponding diene diols which are synthetically versatile building blocks ; Financial support from the AEI (CTQ2017-88451-R), Xunta de Galicia (ED431C 2018/04; Centro singular de investigación de Galicia accreditation 2019–2022, ED431G 2019/03) and the European Union (European Regional Development Fund – ERDF) is gratefully acknowledged. E. R.-C. thanks Xunta de Galicia for predoctoral fellowship ; SI

11 pages, 3 figures, 2 tables.- Published online October 23, 2012 ; Improving knowledge on the apportionment of airborne particulate matter will be useful to handle and fulfill the legislation regarding this pollutant. The main aim of this work was to assess the influence of markers in the source apportionment of airborne PM10, in particular, whether the use of particle polycyclic aromatic hydrocarbon (PAH) and ions provided similar results to the ones obtained using not only the mentioned markers but also gas phase PAH and trace elements. In order to reach this aim, two receptor models: UNMIX and positive matrix factorization were applied to two sets of data in Zaragoza city from airborne PM10, a previously reported campaign (2003-2004) (Callén et al. Chemosphere 76:1120-1129, 2009), where PAH associated to the gas and particle phases, ions and trace elements were used as markers and a long sampling campaign (2001-2009), where only PAH in the particle phase and ions were analyzed. For both campaigns, positive matrix factorization was able to explain a higher number of sources than the UNMIX model. Independently of the sampling campaign and the receptor model used, soil resuspension was the main PM10 source, especially in the warm period (21st March-21st September), where most of the PM10 exceedances were produced. Despite some of the markers of anthropogenic sources were different for both campaigns, common sources associated to different combustion sources (coal, light-oil, heavier-oil, biomass, and traffic) were found and PAH in particle phase and ions seemed to be good markers for the airborne PM10 apportionment. © 2012 Springer-Verlag Berlin Heidelberg. ; Authors would like to thank Aula Dei-CSIC (R. Gracia) for providing the meteorological data and the CSIC for the Ramón y Cajal contract to J.M.L. Authors would also thank the Spanish Government (MICIIN) for the partial financial support of this work through the contract CGL2009-14113-C02-01 and the E plan for the co-funding. ; Peer Reviewed

Accepted 16th November, 2010.- El pdf del artículo es la versión post-print ; Urban areas constitute major pollution sources due to anthropogenic activities located in these areas. Among the legislated air pollutants, the particulate matter with an aerodynamic diameter less than or equal to 10 microns (PM10) and polycyclic aromatic hydrocarbons (PAH) are controlled under Directive 2008/50/EC and Directive 2004/107/EC, respectively due to their adverse health effects. A study was carried out at four urban and rural Spanish areas during the warm and cold seasons in 2008-2009 to quantify 19 PAH associated with the atmospheric PM10 by gas chromatography-mass spectrometry-mass spectrometry detection (GC-MS-MS) with the internal standard method. The particle-bound composition of the analysed PAH was 5 and 10 times greater in industrial and urban areas, respectively when compared to those measured in rural areas. The highest PAH concentrations during the cold period were possibly due to the additional contribution of domestic heating sources and meteorological conditions such as low temperature and solar irradiation. The use of molecular diagnostic ratios indicated that the possible, major PAH pollution sources in the most polluted areas were pyrogenic sources, mainly attributed to petroleum combustion sources (motor vehicle emissions and crude oil combustion). Petrogenic sources related to evaporative emissions also seemed to contribute in the most polluted area during the warm period. Those dates with high carcinogenic character according to the benzo(a)pyrene equivalent (BaP-eq) were also possibly attributed to petroleum combustion sources. © The Royal Society of Chemistry 2011. ; Authors would like to thank Aula Dei-CSIC (R. Gracia), the Government of Aragon (DGA), the Fondo Social Europeo de Desarrollo Regional and the Ministry of Science and Innovation for supporting the project CGL2009-14113-C02-01 and the Ramón y Cajal contract of J.M.L. ; Peer Reviewed

12 pages, 4 figures, 1 table.-- Work presented at the 19th International Conference on Modelling, Monitoring and Management of Air Pollution, 19 - 21 September 2011, Malta. ; Particulate matter samples less than or equal to 10 μm (PM10) were collected by using a high-volume air sampler during cold and warm seasons at two different areas in Spain: a rural area which was considered a "non-polluted" area and an urban city, Zaragoza (Spain) in which vehicular traffic and small industries were the potential pollution sources. The PM10 samples were analyzed to determine their organic (polycyclic aromatic hydrocarbons (PAH) by gas chromatographymass spectrometry mass spectrometry) and inorganic (ions: anions and cations, by ionic chromatography and by inductively coupled plasma optical emission spectroscopy (ICP-OES)) composition. Higher PAH and ions concentrations were obtained in the urban area during the cold season when compared to the warm season and these concentrations were always higher than the ones obtained in the rural area. Fuel combustion sources associated with coal, natural gas, vehicular traffic and biomass combustion were the major anthropogenic PM10 pollution sources obtained by principal component analysis (PCA) in the urban area although natural sources associated with marine aerosol were also contributing to this PM10. Cluster analysis corroborated these sources and allowed classifying samples as a function of the meteorological variables, PAH and ion concentrations. ; Authors would like to thank Aula Dei-CSIC (R. Gracia) for providing the meteorological data, to the Gobierno de Aragón (DGA) for partial financial support, to the Ministry of Science and Innovation (Spain) through the project CGL2009-14113-C02-01 for funding as well as the Fondo Europeo de Desarrollo Regional (FEDER). J.M. López would also like to thank CSIC Spanish Government for his Ramón and Cajal contract.

Copper catalysis allows the direct oxygen alkenylation of dialkyl phosphonates with alkenyl(aryl)iodonium salts with selective transfer of the alkenyl group. This novel methodology proceeds with a wide range of phosphonates under mild conditions and gives straightforward access to valuable enol phosphonates in very good yields. ; Financial support from the AEI (CTQ2017-88451-R), Xunta de Galicia (ED431F 2016/006; ED431C 2018/04; Centro singular de investigación de Galicia accreditation 2016-2019, ED431G/09) and the European Union (ERDF) is gratefully acknowledged. N. V.-G. thanks AEI for a predoctoral FPI fellowship ; SI

Trabajo presentado al 4th International Symposium and IUAPPA Regional Conference: "Air quality mangement at urban, regional and global scales", celebrado en Estambul (Turquía) del 10 al 13 de septiembre de 2012. ; Benzo(a)pyrene (BaP) is polycyclic aromatic hydrocarbon whose adverse effects on human health have been demonstrated. Directive 2004/107/CE of the European Union establishes a target value of 1 ng/m3 of BaP in the atmosphere. The main aim is to estimate the BaP concentrations in the atmosphere and know the main influences on BaP ground level concentrations. BaP degradation and adsorption mechanism have been integrated into the chemical-transport model CMAQ. The air quality model has been driven by the WRF meteorological model. A validation process of the BaP and other pollutant results have been conducted in the urban area of Zaragoza (Spain) during 10 weeks in 2010. The agreement is generally satisfactory. ; Authors would like to thank Aula Dei-CSIC (R. Gracia), the Ministry of Science and Innovation (MICIIN) and the E plan for supporting the project CGL2009-14113-C02-01. J.M. López would also like to thank the MICIIN for his Ramón y Cajal contract. Also to thank Departamento de Medio Ambiente del Gobierno de Aragón, Dirección General del Catastro del Gobierno de Aragón, Sistema de Información Territorial del Gobierno de Aragón and Ayuntamiento de Zaragoza. Authors thankfully acknowledge the computer resources, technical expertise and assistance provided by the Centro de Supercomputación y Visualización de Madrid (CeSVIMa) and the Spanish Supercomputing Network (BSC). ; Peer reviewed

Trabajo presentado a la 15th Conference on Harmonisation within Atmospheric Dispersion Modelling for Regulatory Purposes, celebrada en Madrtid (España) del 6 al 9 de mayo de 2013. ; Benzo(a)pyrene (BaP) is polycyclic aromatic hydrocarbon whose adverse effects on human health have been demonstrated. Directive 2004/107/CE of the European Union establishes a target value of 1 ng/m3 of BaP in the atmosphere. In this contribution we have used the third generation of air quality modelling systems to evaluate the impact of BaP emissions in Zaragoza area (Spain) with 1 km spatial resolution. We have developed the inclusion of the transport, scavenging and deposition processes for the BaP. BaP degradation and adsorption mechanism have also been integrated into the chemical-transport model CMAQ (Community Multiscale Air Quality Modelling System). BaP is injected into the atmosphere as particle.The aerosol-gas partitioning phenomenon in the atmosphere is modelled taking into a count that the concentrations in the gas and the aerosol phases are in equilibrium. The WRF (Weather Research & Forecasting Model)) is also used to provide the meteorological information as input for CMAQ modelling system. A validation process of the BaP and other pollutant results have been conducted in the urban area of Zaragoza (Spain) during 12 weeks since February, 2010 to January, 2011. The agreement is generally satisfactory. ; Authors would like to thank Aula Dei-CSIC (R. Gracia), the Ministry of Science and Innovation (MICIIN) and the E plan for supporting the project CGL2009-14113-C02-01. J.M. López would also like to thank the MICIIN for his Ramón y Cajal contract. Also to thank Departamento de Medio Ambiente del Gobierno de Aragón, Dirección General del Catastro del Gobierno de Aragón, Sistema de Información Territorial del Gobierno de Aragón and Ayuntamiento de Zaragoza. Authors thankfully acknowledge the computer resources, technical expertise and assistance provided by the Centro de Supercomputación y Visualización de Madrid (CeSVIMa) and the Spanish Supercomputing Network (BSC). ; Peer reviewed

9 pages, 6 figures, 3 tables.--Available online 8 December 2013 ; Co-pyrolysis of forestry wastes and waste tyres is carried out using different facilities: a fixed bed reactor and a continuous auger reactor. Remarkably, only one phase is found in the liquid fraction, which is not achieved by mixture of the pure liquids. In addition, positive effects between waste tyre and biomass are evidenced, being more notable even synergetic in the auger reactor. It is found that whilst acidity, density and oxygen content decrease, pH and calorific value increase with respect to the merely biomass pyrolysis liquid, leading to upgraded bio-oil. Upgrading process is linked to the presence of radical interactions between waste tyres and biomass pyrolysis products. In addition, it is observed that the addition of waste tyres to the feedstock blend is significantly decreasing the amount of aldehydes and phenolic compounds, which is beneficial for improving the stability of the new bio-oils. © 2013 Elsevier B.V. ; The authors would like to thank the Aragon Regional Government (DGA) and the Caixa Bank for financial support (Project GA-LC-015/ 2011). The authors also thank MINECO and FEDER funds for providing partial support for this work (project CTQ2012-37984-C02-01). Juan D. Martínez thanks the Fundación Carolina for his fellowship as well as the Enlaza-Mundos Program. Part of the research carried out at UAB has been funded by MICINN (CTQ2009-13873). ; Peer Reviewed