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Self rated health, in adult population, is strongly associated with mortality and life expectancy. In younger people this association is less evident, but it may anticipate a similar risk in adult life. Our research, based on the HBSC (Health Behaviour in School-Aged Children) International collaboration, contributes to deepen the knowledge in this field by monitoring adolescents' health through a multi-national survey involving 29 European countries, plus North America (Canada and USA) and Israel.Following an established methodology, the HBSC survey has elaborated a questionnaire on health and health behaviour, filled in by a representative national sample of 11-, 13- and 15-year-old boys and girls. The sample is constituted of more than 160,000 subjects interviewed during the 2001/2002 survey. Reported symptoms and self-rated health have been analysed by sex and age and through the different countries.Girls resulted to have a poorer perception of their health, with respect to males, at all ages and in all countries (Overall OR = 1.70, 95% CI: 1.66-1.76). Age increases this risk both for males and females, with an average increase of 32% (95% CI: 29-34%) per year in the age-range 11-15. The situation is similar for reported symptoms, with an overall OR of 1.81 (95% CI: 1.77-1.85) for females of reporting three or more symptoms at least once a week; also this risk increases of 26% (95% CI: 24-27%) per year during the pre-adolescence phase. In both cases it could be shown a significant interaction effect between age and gender: OR = 1.19 (CI: 1.15-1.23) for perceived health and OR = 1.26 (CI: 1.23-1.29) for reported symptoms in females with respect to males.Even if adolescence is described as the healthiest period of life, a consistent minority of young people perceive and report a poor health and a high number of symptoms. Females are constantly in a worse position than males and older age groups are worse than younger ones.

DFT Becke3LYP calculations are applied to the computational study of the activation of alkane C−H bonds by metallocarbene homoscorpionate complexes. A total of 16 different combinations of metallocarbene complex and alkane are explored, defined by the use of TpAgC(H)(CO2CH3), TpBr3AgC(H)(CO2CH3), TpCuC(H)(CO2CH3), and TpBr3CuC(H)(CO2CH3) species as metallocarbene and methane, ethane, propane, and butane as alkane. The reaction is found to be under kinetic control, and the selectivity is decided in a step with a low-barrier transition state where the key bond-breaking and bond-forming processes take place in a concerted way. This transition state has several possible conformations, which are systematically explored to find the one with lowest energy for each reaction. Variations of the energy barrier as a function of the nature of metal, ligand, and alkane are analyzed and discussed.

A simple copper-based catalytic system has been developed for the carbon-hydrogen amidation reaction. The copper-homoscorpionate complex Tp(Br3)Cu(NCMe) catalyzes the transfer of the nitrene unit NTs (Ts = p-toluenesulfonyl) and its subsequent insertion into the sp(3) C-H bonds of alkyl aromatic and cyclic ethers or the sp(2) C-H bonds of benzene using PhI=NTs as the nitrene source, affording the corresponding trisubstitued NR(1)HTs amines in moderate to high yields. The use of the environmentally friendly chloramine-T has also proven effective, with the advantage that sodium chloride is formed as the only byproduct. A tandem, one-pot consecutive nitrene-carbene insertion system has been developed to yield amino acid derivatives.

The changing relationships between the G-7 countries are examined through VAR models for quarterly growth, estimated over sub-periods and using a rolling data window. Trivariate models are employed, each including the US and a European (E15) aggregate. The results show that conditional volatility of growth has declined relatively more since 1980 for E15 than for the US, aggregate European shocks have increased impact on “core” European countries from around 1980, the effects of the US on Europe are largest during the 1970s and the late 1990s, and E15 has a steadily increasing impact on the US economy over time.

Facile alkane functionalization by means of the insertion of :CHCO2Et, from ethyl diazoacetate, into carbon−hydrogen bonds mediated by catalytic amounts of (NHC)MCl (NHC = N-heterocyclic ligand; M = Cu, Au) and a halide scavenger MX has been achieved. This chemistry includes the insertion of the carbene fragment into alkane primary positions with Cu- and Au-based catalysts. The nature of the counterion X and of the NHC ligand have a significant effect on the overall yields and regioselectivity of the reaction.

The complexes [TpBr3Ag]2·CH3COCH3 (1) and TpBr3Ag(thf) (2) catalyze the insertion of the :CHCO2Et group from ethyl diazoacetate (EDA) into the saturated C−H bonds of several C5, C6, and C8 linear and branched alkanes. In addition to secondary and/or tertiary sites, the unprecedented insertion into the primary C−H bonds of the substrates studied has been observed with variable regioselectivity, toward the methyl groups, within the range of 40−60% for branched and nearly 25% for linear alkanes.

A new bis(carbon dioxide) adduct of molybdenum containing the tridentate, bis(phosphine) ligand, HN(CH2CH2PMe2)2 (NP2), in a mer conformation has been synthesized and structurally characterized. Its carbonyl carbonate isomer [Mo(CO3)(CO)(NP2)(PMe3)] has also been prepared. In addition, the reactivity of the complex [Mo(CO3)(CO)(PMe3)4] toward CO has been studied, a transformation that has led to the formation of the dicarbonyl complex [Mo(CO3)(CO)2(PMe3)3]. This complex liberates CO2 upon heating under a carbon monoxide atmosphere by means of a CO–CO3 conproportionation reaction. The new trinuclear complex [Mo3(μ2-CO3)(μ2-O)2(O)2(CO)2(H2O)(PMe3)6]·H2O, resulting from the interaction of [Mo(CO3)(CO)(PMe3)4] and water, has been isolated and structurally characterized.

The new complex Tp B r 3 Ir(C 2 H 4 ) 2 , 1, photochemically activates the C-H bonds of n-pentane in a two-step process, the first one being the formation of an isolable alkyl-hydride intermediate of composition Tp B r 3 Ir(H)(C 2 H 4 )(C 5 H 1 1 ), 3a, that subsequently undergoes β-hydride elimination to generate a terminal olefin complex, Tp B r 3 Ir(H) 2 (C 5 H 1 0 ), 4a. The reaction can also be extended to diethyl ether. In this case, the reaction proceeds by the activation of one of the β-C-H bonds (with respect to the O-ether atom) with formation of the alkyl-hydride 3b and the dehydrogenation product 4b. These processes also compete with the intramolecular C-H activation of one of the coordinated ethylene ligand by the Ir(I) center in 1, which affords the hydride-vinyl complex TpBr3Ir(H)(CH=CH 2 )(C 2 H 4 ), 2. Attempts to thermally induce the above transformations has led to the exclusive formation of a mixture of the hydride-α,ω-butenyl complex Tp B r 3 Ir(H)(CH 2 CH 2 CH=CH 2 ), 5, and the hydride-crotyl complex Tp B r 3 Ir(H)(C 4 H 7 ), 6.

Complexes of general formula TpxCu (Tpx = homoscorpionate ligand) have been employed as catalysts for the insertion of ethyl diazoacetate into C−H bonds of a variety of hydrocarbons and ethers, in moderate to high yields: tertiary, secondary, and primary C−H bonds have been functionalized by this methodology. Particularly interesting is the homologation of O-methyl groups in ethers, which has been achieved for a group of substrates. The existence of electron-withdrawing groups in the Tpx ligand seems to be crucial for the activity and the selectivity of the catalyst.

The complexes TpXCu (TpX = homoscorpionate ligands) efficiently catalyze the insertion of the carbene fragment :CHCO2Et, generated from ethyl diazoacetate, into the OH bond of saturated and unsatur...

El objetivo de este estudio es examinar las relaciones entre estrés de rol, engagement y satisfacción laboral de acuerdo con el modelo demandas-recursos laborales. El modelo propuesto plantea que el engagement media la relación entre ambigüedad, conflicto y sobrecarga de rol, por un lado y satisfacción en el trabajo, por el otro. Para verificar el modelo, se obtuvieron datos de una muestra de 586 trabajadores del sur de Espana˜ (Medad = 37.11, 50% mujeres). El ajuste del modelo y de la mediación se realizaron mediante un modelo de ecuaciones estructurales (path analysis). Los resultados mostraron que el conflicto de rol y la ambigüedad de rol junto con el engagement fueron predictores significativos de la satisfacción laboral. No obstante, el engagement no medió la relación entre el estrés de rol y la satisfacción laboral. El estrés de rol como demanda obstaculizadora explicaría el mayor impacto directo sobre la satisfacción que a través del engagement. Se proponen implicaciones prácticas y futuras investigaciones, The aim of this study is to examine the relationship between role stress, work engagement, and job satisfaction according to the Job Demands-Resources Model. The proposed model hypothesizes that work engagement mediates the relationship between role ambiguity, role conflict, and role overload on one hand, and job satisfaction on the other. To test the model, data was collected from 586 workers from southern Spain (Mage = 37.11, 50% women). Model fit and mediation test were examined using structural equation modeling (path analysis). Results showed that role conflict, role ambiguity, and work engagement were significant predictors of job satisfaction. However, work engagement did not mediate the relationship between role stress and job satisfaction. Role stress as a hindrance job demand would explain the most direct impact on job satisfaction than through work engagement. Implications for practice and future research are considered

The [3 + 2] cycloaddition of electron deficient N-carbamoyl azides (II) and (IV) with alkynes (I) is realized for the first time using a copper-based catalyst system.

A novel carbene transfer reaction from diazoesters to carboxylic acids is developed using a highly fluorinated tris(indazolyl)borate silver complex as catalyst.

International audience; Copper–carbene [TpxCu=C(Ph)(CO2Et)] and copper–diazo adducts [TpxCuη1-N2C(Ph)(CO2Et)] have been detected and characterized in the context of the catalytic functionalization of O–H bonds through carbene insertion by using N2=C(Ph)(CO2Et) as the carbene source. These are the first examples of these type of complexes in which the copper center bears a tridentate ligand and displays a tetrahedral geometry. The relevance of these complexes in the catalytic cycle has been assessed by NMR spectroscopy, and kinetic studies have demonstrated that the N-bound diazo adduct is a dormant species and is not en route to the formation of the copper–carbene intermediate.

A polystyrene-linked tris(triazolyl)methanecopper(I) cationic catalyst operates under heterogeneous conditions for the reaction of ethyl diazoacetate (EDA) with an array of substrates. Carbon–hydrogen as well as X–H (X ¼ O, N) functionalization derived from the formal transfer of the carbene moiety (:CHCO2Et) from the copper center and subsequent insertion have been achieved, the reactions permitting repeated catalyst recycling and reuse. The addition of the same carbene unit to benzene leading to a cycloheptatriene derivative (B¨uchner reaction) or to phenylacetylene (cyclopropenation) took place at similar rates to the insertion processes and with the same catalyst recyclability. The use of this heterogenized cationic Cu catalyst in continuous flow has also been implemented. Key characteristics of the flow process are its high and constant turnover frequency (TOF) (residence times of 1 min still lead to full conversion in the reaction with ethanol after 48 h operation) and its suitability for the sequential performance of different types of carbene transfer reactions with a simple and affordable experimental setup., This work was funded by MINECO (grants CTQ2011-28942-C02-01 and CTQ2012-38594-C02-01), DEC-Generalitat de Catalunya (Grant 2014SGR827), Junta de Andalucia (P10-FQM-06292) and ICIQ Foundation. The ICIQ team also thanks MINECO for support through Severo Ochoa Excellence Accreditation 2014-2018 (SEV-2013-0319). L. M. thanks MECD for a FPU fellowship. E. O. thanks ICIQ for a postdoctoral fellowship. C. A. thanks MINECO for a Juan de la Cierva posdoctoral fellowship.

Nucleophilic attack of the β-carbon of an Ir I I I -alkenyl functionality onto the α-carbon of a coordinated nitrile- or aldehyde occurs intramoleculary to yield initially iridacyclic structures. Nitriles give rise to isolable complexes that contain delocalized five-membered rings (iridapyrroles, e.g. 3'-8') in a reaction catalyzed by H 2 O (for some of these syntheses, Ir I I I -η 3 -allyl derivatives may be used as the source of the Ir I I I -alkenyl moiety). In contrast. the alkenyl-to-aldehyde C-C coupling gives transient iridacycles that evolve by a fast alkyl-to-alkylidene migration and β-H elimination. The end products (13* and 14*) contain an elaborated chelating alkoxide-olefin ligand. Addition of [H(OEt 2 ) 2 ](BAr' 4 ] to the iridapyrroles effects stereospecific protonation of the β-ring carbon. Those iridapyrroles which contain an additional metal-alkyl functionality (e.g. 3a*, alkyl=C 2 H 5 ) afford highly reactive cationic alkyl-alkylidene intermediates that evolve instantaneously by migratory insertion/β-H elimination. The end products also contain an elaborated, chelating ligand, although this time with an olefin and imine terminus compared with the previous ligand. Contrary to this result, protonation of the hydride-iridapyrrole complex 8a* in weakly coordinating solvents permits isolation of two unusual cationic cis-hydride-alkylidene compounds 11*, which undergo reversible 1,2-H shifts.

This work centers on the study of the image of universities, with the aims of explaining the process of image forming by means of its different components, both in its cognitive and affective dimensions and of analyzing its relationship with the students’ satisfaction with the university. The results of the empirical work carried out on a representative sample of 6,775 students studying at a Spanish university demonstrate that the cognitive component of image is an antecedent of the affective component. In turn, both of those components influence the forming of the overall image of the university and the cognitive, affective and overall images statistically and significantly influence the students’ satisfaction with the university.

After the first step a cyclopropane intermediate is obtained which is directly converted to indole derivatives (III), (VI), (VII), and (IX) after silica gel column chromatography.

Silver complexes bearing trispyrazolylborate ligands (Tpx) catalyze the aziridination of 2,4-diene-1-ols in a chemo-, regio-, and stereoselective manner to give vinylaziridines in high yields by means of the metal-mediated transfer of NTs (Ts = p-toluensulfonyl) units from PhI═NTs. The preferential aziridination occurs at the double bond neighboring to the hydroxyl end in ca. 9:1 ratios that assessed a very high degree of regioselectivity. The reaction with the silver-based catalysts proceeds in a stereospecific manner, i.e., the initial configuration of the C═C bond is maintained in the aziridine product (cis or trans). The degree of regioselectivity was explained with the aid of DFT studies, where the directing effect of the OH group of 2,4-diene-1-ols plays a key role. Effective strategies for ring-opening of the new aziridines, deprotection of the Ts group, and subsequent formation of β-amino alcohols have also been developed.

Two copper complexes for the regioselective formation of 2,5-disubstituted oxazoles from carbonyl azides and terminal alkynes are developed.

Homoscorpionate ligands, with organic sulfides as cocatalyst, promote the reaction of phenyldiazomethane (II) with aldehydes (I) to form epoxides (III), with activities exceeding or, at least similar to those of reported rhodium-based systems.

The kinetics of the electron transfer reactions between pentaammine(pyrazine)ruthenium(II), [Ru(NH3)5pz]2+ and tris(oxalate)cobalt(III), [Co(C2O4)3]3− and pentaammine(pyridine)ruthenium(II), [Ru(NH3)5py]2+ and tetraammine(pyrazinecarboxylate)cobalt(III), [Co(NH3)4pzCO2]2+ have been studied in aqueous solutions of DNA over the concentration ranges 0 to 2.46 × 10−3 mol dm−3 and 1.23 × 10−4 to 1.00 × 10−3 mol dm−3, respectively. The results are interpreted on the basis of a modified pseudophase model which takes into account the anticooperative character of the binding of the cationic reactants to DNA.

The preparation of (DIPPP)Pd(PR3) and [(DIPPP)(PR3)PdH][OR‘] (DIPPP = bis(1,3-diisopropylphosphino)propane; R = Cy, Et; R‘ = Ar, CF3SO2) is reported. (DIPPP)Pd(PCy3) and [(DIPPP)(PCy3)PdH][CF3SO3] have been structurally characterized. (DIPPP)Pd(PR3) complexes catalyze the reaction of ethylene with carbon monoxide and phenols to give aryl propionates. In situ 31P NMR experiments have shown that the resting state of the catalyst in these transformations is the binuclear species [{(DIPPP)Pd}2(μ-H)(μ-CO)][OPh].

The fixation of the preformed polypyrazolylborate copper(I) complexes BpCu (1), Tp*Cu (2), and [B(pz)4]Cu (3) (Bp = dihydrobispyrazolylborate, H2B(pz)2; Tp* = hydrotris(3,5-dimethyl)pyrazolylborate, HB(pz*)3; B(pz)4 = tetrakispyrazolylborate) on silica gel and their use, under heterogeneous conditions, as catalysts for the olefin cyclopropanation reaction are reported. The catalytic activity is very similar to that observed under homogeneous conditions, as a consequence, according to the studies presented herein, of a ligand-to-support interaction that would involve the hydroxyl groups of the silica surface and the borohydride B−H group and/or the pyrazolyl nitrogen atoms. The strength of such interactions allows the recovery and recycling of the supported catalysts for a number of cycles.

N-donor Lewis bases such as acetonitrile or pyridine react with the Rh(I) compound TpMe2Rh(C2H4)2 (1) to give the Rh(III) derivatives TpMe2Rh(CHCH2)(C2H5)(L) (2, 3) as the kinetic products of the reactions. Upon heating at 60 °C, the acetonitrile adduct 2 converts into TpMe2Rh(C2H4)(NCMe) (5). Under similar conditions, 2 is able to induce the activation of one of the C−H bonds of C6H6, in a process that involves the intermediacy of 1, as demonstrated by isotopic labeling studies. The phosphine adducts TpMe2Rh(C2H4)(PR3) (R = Me, Et) are also efficient reagents for the C−H bond activation of C6H6, py, or thiophene. In the latter case, rupture of the C−S bond is also detected, although the C−S bond activation complexes are thermodynamically disfavored with respect to those derived from the cleavage of one of the α-C−H bonds.

Kinetic studies of the ethyl diazoacetate (EDA) decomposition reaction in the presence of BpCu (1) and in the presence or absence of olefin have led to the determination of several kinetic and thermodynamic parameters, and a consistent mechanism has been proposed for the olefin cyclopropanation reaction. Related studies with the complexes [Cu(bipy)2]I (bipy = bipyridine) and [Cu(bis(oxazoline))2]OTf have shown strong similarities with the results obtained with 1. A general mechanism covering the copper-based systems reported in the literature has been proposed, the real catalyst (i.e., the species to be reacted with EDA) in all cases being a neutral, 14-electron fragment of composition (L−L)Cu (L−L = Bp- and Tp-like ligands, semicorrins, salicylaldehyde derivatives) or, alternatively, the isoelectronic, cationic [(L−L)Cu]+ (for L−L = bis(oxazoline), bipyridine).

Styrene can be polymerized at room temperature in the presence of equimolar mixtures of the gold(III) complexes (NHC)AuBr3 (NHC = N-heterocyclic carbene ligand) and NaBAr'4, in the first example of a gold-induced olefin polymerization reaction.

An unusual Fischer carbene derivative that, in addition, contains an alkyl and a hydride ligand is obtained by C−H bond activation of THF by the hydride–vinyl species [TpMe2IrH(CHCH2) (C2H4)]. This complex is also capable of activating the C−H bonds of benzene to give remarkably stable IrIII–N2 complexes (see illustration).

The complexes BpCu (1), BpCuL (L = bipy, 2; L = Ph2PCH2CH2PPh2, 3; L = PCy3, 4) and BpCuL2 (L = py, 5; L = PPh3, 6) catalyze the cyclopropanation of olefins in moderate to high yields in the homoge...

The formation and some substitution chemistry of the bis(ethylene) complexes Bp′Rh(C2H4)2 (Bp′ - Bp*; 1*; Bp′ - Bp, 1) are described. Reaction of 1* with 1 equiv. of N-donor ligands or monodentate phosphines (L) leads to the isolation of compounds of general formula Bp*Rh(C2H4)(L). Addition of an excess of amine produces the eighteen electron complexes Bp*Rh(C2H4)(L)2 whereas in the case of the PR3 ligands the second equivalent of the donor gives the disubstituted sixteen electron compounds Bp*Rh(L)2. The ethylene groups in 1* and 1 can also be replaced by carbon monoxide and tert-butyl isocyanide, affording the complexes Bp′Rh(L)2 (L - CO, CN1Bu). The solid state structures of the compounds Bp*Rh(C2H4)2 (1*) and BpRh(PPh3)2 (9) have been determined by X-ray diffraction studies. Crystals of 1* are monoclinic, space group P21/c, with a = 15.129(3), b = 17.501(3), c = 13.425(8) A, β = 111.02(4)°, V = 3318(2) A3, and Dcalc = 1.06 g cm 3 for Z = 8; R = 4.3 and Rw = 4.4. Crystals of 9 are triclinic, space group P21/c, with a = 10.281(2), b = 11.637(2), c = 17.836(8) A, α = 90.09(2), β = 95.77(2), γ = 108.410(13)°, V = 2013(2) A3, and Dcalc = 1.4 g cm 3 for Z = 2; R = 0.0302 and wR = 0.0787.

A number of cationic gold(I) complexes have been synthesized and found to be stabilized by the use of N-heterocyclic carbene ligands. These species are often employed as in situ-generated reactive intermediates in gold catalyzed organic transformations. An isolated, well-defined species was tested in gold-mediated carbene transfer reactions from ethyl diazoacetate.

Review: different methodologies to activate methane with transition metal complexes as well as few examples of the catalytic functionalization of methane; 60 refs.

© 2014 American Chemical Society. A novel reaction involving benzoxazole, ethyl diazoacetate, and water has been discovered, with TpBr3Cu(NCMe) (TpBr3 = hydrotris(3,4,5-tribromopyrazolyl)borate) as the catalyst. The fused azoles are converted into highly functionalized substituted benzenes bearing aldehyde, amine carboxylate and hydroxyl groups. The protocol has been applied for a series of benzoxazoles with several diazo compounds. Experimental data and theoretical calculations have led to a mechanistic proposal that includes carbene addition, ylide formation, and water addition to the latter, all those steps being catalyzed by the copper center.

Silver complexes bearing trispyrazolylborate ligands (Tp(x)) catalyze the aziridination of 2,4-diene-1-ols in a chemo-, regio-, and stereoselective manner to give vinylaziridines in high yields by means of the metal-mediated transfer of NTs (Ts = p-toluensulfonyl) units from PhI═NTs. The preferential aziridination occurs at the double bond neighboring to the hydroxyl end in ca. 9:1 ratios that assessed a very high degree of regioselectivity. The reaction with the silver-based catalysts proceeds in a stereospecific manner, i.e., the initial configuration of the C═C bond is maintained in the aziridine product (cis or trans). The degree of regioselectivity was explained with the aid of DFT studies, where the directing effect of the OH group of 2,4-diene-1-ols plays a key role. Effective strategies for ring-opening of the new aziridines, deprotection of the Ts group, and subsequent formation of β-amino alcohols have also been developed.

Electron deficient azides are challenging substrates in CuAAC reactions. Particularly, when N-carbonyl azides are applied the formation of N-carbonyl triazoles has not yet been observed. We report herein the first example of this class of reaction, with a copper-based system that efficiently enables the synthesis of N-carbamoyl 1,2,3-triazoles by [3+2] cycloaddition of N-carbamoyl azides and alkynes

The bis(ethene) complex [Tp*Ir-(C2H4)2] (1*) (Tp* = tris(3,5-dimethyl-1-pyrazol-1-yl)hydroborato) undergoes thermal rearrangement to the hydrido–allyl complex [Tp*IrH(π3-C3H4Me)] (6*), through the intermediacy of the hydrido–vinyl complex [Tp*IrH(C2H3)(C2H4)] (2*). The overall conversion of 1* into 6* corresponds formally to the dimerisation of ethene by an unprecedented pathway that involves sequential C–H bond activation of a coordinated olefin molecule and C–C bond formation by coupling of the resulting vinyl and ethene moieties. Similar transformations have been observed for monosubstituted olefins like propene and 1-butene, while the internal alkene cis−2-butene experiences allylic activation of an sp3 C–H bond, which provides an alternative route to 6*. The extension of these investigations to the analogous complexes of the unsubstituted tris(pyrazolyl)hydroborato ligand Tp is also reported. Mechanistic studies on the formation of the C–C bond by coupling of the vinyl and the olefin ligands suggest the participation of a vinylidene complex (formed by α-H abstraction from the vinyl group), which then rearranges to an allene species. Evidence for the involvement of these and other key reaction intermediates is provided.

We have analysed the effects of 7,12-O-diacetyl-8-O-benzoil-2,3-diepiingol (DBI), an ingol derivative isolated from E. canariensis, on isometric tension developed by isolated rabbit basilar and carotid arteries. Concentration-response curves to DBI (10−8 - 3 × 10−5 m) were obtained cumulatively in both arteries at resting tension and active tone (KC1, 50 mm). At resting tension, DBI induced a concentration-dependent contraction, which was not inhibited in Ca2+-free medium. H7 (1-(5-isoquinoline sulphonyl)-2-methylpiperazine dichloride) (10−4 m) inhibited the DBI-induced contraction both in basilar and in carotid arteries. Calmidazolium (10−4 m) inhibited the maximum contraction of the carotid artery to DBI, and completely abolished the response in the basilar artery. In pre-contracted basilar arteries DBI induced a concentration-dependent relaxation that was not modified by incubation with NG-nitro-l-arginine (l-NOARG; 10−5 m) or indomethacin (10−5 m). In the carotid artery with active tone DBI induced further contractions, which were not significantly modified by l-NOARG (10−5 m) and were potentiated by indomethacin (10−5 m). These results suggest that DBI contracts rabbit basilar and carotid arteries by a mechanism that is independent of extracellular Ca2+ and involves the participation both of protein kinase C and of calmodulin. DBI relaxes basilar but not carotid arteries by a mechanism independent of the liberation of nitric oxide and prostacyclin. In the carotid artery prostacyclin but not nitric oxide partially counteracts the contractile action of DBI.

The dehydrogenation of n-hexane and cycloalkanes giving n-hexene and cycloalkenes has been observed in the reaction of such hydrocarbons with hydrogen peroxide, in the presence of copper complexes bearing trispyrazolylborate ligands. This catalytic transformation provides the typical oxidation products (alcohol and ketones) with small amounts of the alkenes, a novel feature in this kind of oxidative processes. Experimental data exclude the participation of hydroxyl radicals derived from Fenton-like reaction mechanisms. DFT studies support a copper-oxo active species, which initiates the reaction by H abstraction. Spin crossover from the triplet to the singlet state, which is required to recover the catalyst, yields the major hydroxylation and minor dehydrogenation products. Further calculations suggested that the superoxo and hydroperoxo species are less reactive than the oxo. A complete mechanistic proposal in agreement with all experimental and computational data is proposed.

We examined the ability of TpxM (Tpx = hydrotris(pyrazolyl)borate ligand; M = Cu and Ag) and IPrMCl (IPr = 1,3-bis(diisopropylphenyl)imidazol-2-ylidene; M = Cu, Ag, Au) complexes as catalyst precursors for the cross-coupling of diazo compounds. Experimental data showed that the metal centre can be tuned with the appropriate selection of the ligand to yield either the homo- or hetero-coupling (cross-coupling) products. A computational study of the reaction mechanism allowed the rationalization of the experimental reactivity patterns, and the identification of the key reaction step controlling the selectivity: the initial reaction between the metallocarbene intermediate and one of the diazo compounds. This journal is © 2013 The Royal Society of Chemistry.

Epoxides have been obtained from alde-hydes and phenyldiazomethane using catalytic amounts of both the copper homoscorpionate com-plexes Tp xCuL (Tpx = homoscorpionate ligand; L = acetonitrile or tetrahydrofuran, THF) and dimethyl sulfide (SMe2) in high yields and diasteroselectivities, and with activities higher (TOF = 46 h-1) than those already known with rhodium-or copper-based cata-lysts. Among the copper(I) homoscorpionate com-plexes tested, TpBr3Cu(NCCH 3) showed the highest catalytic activity under mild conditions. The catalytic activity is controlled by electronic effects induced by the Tp x ligand as well as by the stability of the TpxCu(SR 2) adducts. Indeed, in the case of TpMs as ligand, the TpMsCu(THT) (THT = tetrahydrothio-phene) and Tp MsCu(SMe2) species could be isolated as very stable crystalline solids, the molecular struc-ture of the former being confirmed by single-crystal X-ray diffraction analysis. The in situ generation of PhCHN 2 from benzaldehyde tosylhydrazone sodium salt at 60 °C in methyl tert-butyl ether as solvent and TpMsCu(THF) as the catalyst also showed high cata-lytic activities, improving those already reported with copper-based catalysts. © 2013 Wiley-VCH Verlag GmbH&Co. KGaA, Weinheim.

The complexes F(n)-Tp(4Bo,3Rf)Ag(L) (F(n)-Tp(4Bo,3Rf)=a perfluorinated hydrotris(indazolyl) borate ligand; L=acetone or tetrahydrofuran) efficiently catalyze the functionalization of non-activated alkanes such as hexane, 2,3-dimethylbutane, or 2-methylpentane by insertion of CHCO(2)Et units (from N(2)CHCO(2)Et, ethyl diazoacetate, EDA) into their C-H bonds. The reactions are quantitative (EDA-based), with no byproducts derived from diazo coupling being formed. In the case of hexane, the functionalization of the methyl C-H bonds has been achieved with the highest regioselectivity known to date with this diazo compound. This catalytic system also operates under biphasic conditions by using fluorous solvents such as Fomblin or perfluorophenanthrene. Several cycles of catalyst recovery and reuse have been performed, with identical chemo- and regioselectivities.

The sodium amalgam reduction of [MoCl3(PEt3)3] prepared in situ, under 2–3 atm of N2, yielded the dimeric complex [{Mo(N2)2(PEt3)3}2(µ-N2)]1, which reacted with 3 and with 4 equivalents of PMe3 to produce trans-[Mo(N2)2(PMe3)3(PEt3)]2 and trans-[Mo(N2)2(PMe3)4]3, respectively. In the presence of an excess of PMe3(>5 equivalents, under Ar) the known [Mo(N2)(PMe3)5]4a was the final product. This synthetic methodology allowed the preparation, for the first time, of the pure trans-bis(dinitrogen) compound 3. Complexes of the type [Mo(N2)(PMe3)3(L–L)](L–L = Me2PCH2PMe24b, Me2PCH2CH2PMe24c or Et2PCH2CH2PEt24d) and [Mo(N2)(PMe3){N(CH2CH2PMe2)3}]4e were also synthesized and structurally characterized by spectroscopic methods. Upon reaction with C2H4, under mild conditions, 1 gave the bis(butadiene) derivative [Mo(η4C4H6)2(PEt3)2]5a. Protonation of 5a, and of its PMe2Ph analogue 5b, produced the cationic but-2-enyls [[graphic omitted]CHCHCH2)(η4-C4H6)L2][BF4](L = PEt36a or PMe2Ph 6b) in which the butenyl ligand exhibits the classical η3-allylic co-ordination in addition to an agostic Me–Mo interaction. Compounds 4a and 6a were structurally characterized by X-ray crystallography. The Mo atom of 4a resides on a crystallographic mirror plane and is bound to the N2 moiety with a Mo–N separation of 2.02(3)A. The Mo–C and Mo–H separations within the agostic unit of 6a are 2.48(2) and 1.9(2)A, respectively.

The complexes TpBr3Cu(NCMe) (1) and TpMsCu (2) catalyze the addition of the :CHCO2Et unit (generated from N2CHCO2Et, EDA) to benzene to give a cycloheptatriene ring, in analogy with the Buchner reaction. When alkyl groups are attached to the aromatic rings, the selectivity of the reaction can be oriented toward addition or, alternatively, to the insertion into an alkyl C−H bond by using 1 or 2, respectively.

A novel synthetic entry to the title compounds from readily available starting materials is described.

The framework of this research is the study of prejudice between autochthonous and immigrant people. Its aim is to conduct a study of the psychometric properties of a new measure of prejudice attitude for differ- ent groups (majority and minority groups), the Prejudice Attitude Test (PAT). The PAT is based on a conceptual design of attitude with three di- mensions: cognitive, emotional and conative. This work shows the results of reliability estimates and the study of validity evidences (internal struc- ture). Sample was formed by 1967 participants: there were 992 Spanish, 500 Romanian and 475 Ecuadorian people. The sample was selected in 12 municipalities with high rates of immigrant people in their census, chosen in four autonomous communities of Spain's Mediterranean zone. The PAT shows psychometric properties suitable for its use both in majority and in minority groups: an adequate reliability, a substantive internal structure that are consistent with the construct underlying the test.