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The rare organocopper(II) complex [Cu(Metren)(CHCN)] (Metren = tris(2-(dimethylamino)ethyl)amine) has emerged as an important model of potential byproducts in copper-catalyzed atom transfer radical polymerization. This complex has been generated by controlled potential electrolysis of [Cu(Metren)(NCMe)] in the presence of BrCHCN. Time-resolved UV-vis and continuous wave and pulse electron paramagnetic resonance (EPR) spectra identified [Cu(Metren)Br] as an intermediate. Hyperfine sublevel correlation and electron nuclear double resonance spectroscopy of samples at different timepoints reveal signals that are assigned to a C-bound cyanomethylate ligand, with distinct N and H hyperfine coupling constants in comparison with the corresponding N-bound acetonitrile and bromido complexes. The experimental EPR data are supported by density functional theory calculations to understand how the geometries of the species involved produce distinct spectroscopic signatures, and a clear picture of how this unusual organocopper(II) complex is formed has emerged.

Organocopper(ii) complexes are a rarity while organocopper(i) complexes are commonplace in chemical synthesis. In the course of building a strategy to generate organocopper(ii) species utilizing electrochemistry, a method to form compounds with Cu

The preparation of a series of alkali-metal inclusion complexes of the molecular cube [{CoIII(Me3-tacn)}4{FeII(CN)6}4]4– (Me3-tacn = 1,4,7-trimethyl-1,4,7-triazacyclononane), a mixed-valent Prussian Blue analogue bearing bridging cyanido ligands, has been achieved by following a redox-triggered self-assembly process. The molecular cubes are extremely robust and soluble in aqueous media ranging from 5 M [H+] to 2 M [OH–]. All the complexes have been characterized by the standard mass spectometry, UV–vis, inductively coupled plasma, multinuclear NMR spectroscopy, and electrochemistry. Furthermore, X-ray diffraction analysis of the sodium and lithium salts has also been achieved, and the inclusion of moieties of the form {M–OH2}+ (M = Li, Na) is confirmed. These inclusion complexes in aqueous solution are rather inert to cation exchange and are characterized by a significant decrease in acidity of the confined water molecule due to hydrogen bonding inside the cubic cage. Exchange of the encapsulated cationic {M–OH2}+ or M+ units by other alkali metals has also been studied from a kineticomechanistic perspective at different concentrations, temperatures, ionic strengths, and pressures. In all cases, the thermal and pressure activation parameters obtained agree with a process that is dominated by differences in hydration of the cations entering and exiting the cage, although the size of the portal enabling the exchange also plays a determinant role, thus not allowing the large Cs+ cation to enter. All the exchange substitutions studied follow a thermodynamic sequence that relates with the size and polarizing capability of the different alkali cations; even so, the process can be reversed, allowing the entry of {Li–OH2}+ units upon adsorption of the cube on an anion exchange resin and subsequent washing with a Li+ solution., A series of alkali-metal inclusion complexes of the molecular cube [{CoIII(Me3-tacn)}4{FeII(CN)6}4]}]4− have been achieved by following a redox-triggered self-assembly process. The alkali metals are encapsulated in an inert fashion as cationic {M−OH2}+ or M+ units, which can be exchanged in a process that has been studied kineticomechanistically.

The preparation of a series of alkali-metal inclusion complexes of the molecular cube [{CoIII(Me3-tacn)}4{FeII(CN)6}4]4- (Me3-tacn = 1,4,7-trimethyl-1,4,7-triazacyclononane), a mixed-valent Prussian Blue analogue bearing bridging cyanido ligands, has been achieved by following a redox-triggered self-assembly process. The molecular cubes are extremely robust and soluble in aqueous media ranging from 5 M [H+] to 2 M [OH-]. All the complexes have been characterized by the standard mass spectometry, UV-vis, inductively coupled plasma, multinuclear NMR spectroscopy, and electrochemistry. Furthermore, X-ray diffraction analysis of the sodium and lithium salts has also been achieved, and the inclusion of moieties of the form {M-OH2}+ (M = Li, Na) is confirmed. These inclusion complexes in aqueous solution are rather inert to cation exchange and are characterized by a significant decrease in acidity of the confined water molecule due to hydrogen bonding inside the cubic cage. Exchange of the encapsulated cationic {M-OH2}+ or M+ units by other alkali metals has also been studied from a kineticomechanistic perspective at different concentrations, temperatures, ionic strengths, and pressures. In all cases, the thermal and pressure activation parameters obtained agree with a process that is dominated by differences in hydration of the cations entering and exiting the cage, although the size of the portal enabling the exchange also plays a determinant role, thus not allowing the large Cs+ cation to enter. All the exchange substitutions studied follow a thermodynamic sequence that relates with the size and polarizing capability of the different alkali cations; even so, the process can be reversed, allowing the entry of {Li-OH2}+ units upon adsorption of the cube on an anion exchange resin and subsequent washing with a Li+ solution., Financial support by Grant PID2019-107006GB-C21 funded by MCIN/AEI/10.13039/501100011033 is acknowledged.

Novel types of water-soluble anionic cubic cages, K4[{CoIII(Me3-Tacn)}4{FeII(CN)6}4] and Na4[{CoIII(Me3-Tacn)}4{FeII(CN)6}4] (Me3-Tacn = 1,4,7-trimethyl-1,4,7-triazacyclononane), were prepared by means of a mechanistically designed self-assembly process between [Co(Me3-Tacn)Cl3] and A4[FeII(CN)6] (M = Na or K), consisting of a rate-limiting outer-sphere redox step, followed by a fast substitution/inner-sphere redox reaction sequence. These compounds show remarkable stability in aqueous solution at different pH ranges, displaying neat protonation processes and reversible oxidation with peroxodisulfate to its neutral {FeIII4CoIII4} form. Furthermore, the cages behave as a robust and water-soluble molecular Prussian Blue analogue capable of encapsulating {Na-OH2}+ pairs and K+ cations in aqueous solution, with the cubic structure of the complex being preserved. Substitution of the {Na-OH2}+ pairs by K+ is easily accomplished, and the electrochemical properties of the sodium and potassium salts of the new cages have been found to be dramatically dependent on the encapsulated units.

Air oxidation of methanolic solutions of biologically active tridentate pyridyl thiosemicarbazone (TSC) complexes of the general formula [FeII(TSC)2] has been studied at varying dioxygen concentrations, temperatures, and pressures. The data collected indicate that the activation entropy of the reaction increases linearly with the redox potential of the complexes in a more definite way than the activation enthalpy. However, a very distinct behavior is observed for the values of the activation volumes, which do not follow the expected entropy-volume parallel trend for all of the systems studied. The involvement of important interactions between the terminal NH groups of the coordinated TSC ligand and molecular dioxygen has been found to be significant by measurements carried out at varying hydrostatic pressures. Kinetic experiments run on analogous N-deuterated complexes confirm the importance of these noncovalent interactions, which are weaker for the less acidic ND groups. These interactions show the existence of an ordering/expansion process upon going from the reactants to the transition state, whenever an interaction between the polar terminal amino groups and dioxygen can be established.

The kinetics of oxidation of different biologically-active FeII bis-thiosemicarbazone complexes in water has been monitored at varying dioxygen concentration, temperature, pressure, and pH. The oxidation reactions observed can be resolved as a single-step process, producing the expected ferric complex, with rates increasing with decreasing pH. From the pH-dependence of the observed rate constants, a rate law with two terms can be derived, one of them being independent of the acid concentration and the other term showing a saturation behaviour with respect to [H+]. These results indicate the existence of two parallel pathways for oxidation: the acid-independent pathway is only operative for the complexes with ligands bearing terminal, non-coordinated, unsubstituted amines, whereas the term with a [H+]-limiting kinetic behaviour is observed for all the complexes and indicates that the reacting species has to be protonated prior to the oxidation step. From the data collected, the rate law and the thermal and pressure activation parameters have been used to interpret the operating reaction mechanisms. Given the fact that the empirical trends rule out an outer-sphere oxidation process, DFT calculations have been carried out to explain the results and suggest the likely formation, under steady-state very low concentration conditions, of FeIII superoxo and hydroperoxo intermediates.

espanolSe actualiza el catalogo y la distribucion del orden Odonata en la Region de Murcia, comparandolo a uno anterior realizado en los anos 50 del siglo XX. Los resultados indican que a mitad del siglo pasado se localizaron 40 especies en 17 localidades, mientras que las 2.087 citas recopiladas entre 1991-2017 confirman la presencia de 47 especies en 191 localidades. Se han identificado 11 nuevas especies para la Region de Murcia, que se pueden haber visto favorecidas por la construccion de charcas, embalses y otras infraes- tructuras para abastecer a las 225.000 ha de regadios. De ellas, 9 especies se estan expan- diendo su area de distribucion hacia el norte de Europa y/o Asia, efecto que podria estar relacionado con el proceso de cambio climatico actual. Por el contrario, en la revision actual no han sido detectadas 4 especies citadas en el estudio realizado a mediados del siglo XX. euskaraMurtziako eskualdean Odonata ordenaren katalogoa eta banaketa eguneratzen da, lehenago XX. mendeko 50eko hamarkadan egindako batekin alderatuta. Bildutako emaitzen arabera, aurreko mendeko erdialdean, 17 eremutan 40 espezie zerrendatu ziren; aldiz, 1991-2017 urteen artean bildutako 2.087 aipuek 191 eremutan 47 espezieren pre- sentzia egiaztatzen dute. Murtziako eskualderako 11 espezie berri identifikatu dira, 225.000 ha ureztatzeko sortu diren azpiegitura, urtegi zein putzuek mesede egin ahal izan diete. Espezie horietatik bederatzik, euren banaketa area zabaltzen ari dira Europa iparraldera edota Asia aldera, egun gertatzen ari den aldaketa klimatikoaren prozesuaren eraginez. Aldiz, XX. mende erdialdean gauzatutako ikerketan aipatutako lau espezie ez dira berrikuspen berrian topatu. EnglishThe catalogue and distribution of the Odonata order in the Murcia Region has been upda- ted, comparing this to an earlier one made in the 1950s. The results indicate that 40 species were located in 17 localities in the mid-20th century, while the 2087 citations collected between 1991-2017 confirm the presence of 47 species in 191 localities. 11 new species have been identified for the Region of Murcia, which may have been favoured by the construction of ponds, reservoirs and other infrastructures to supply 225,000 hectares of irrigated land. Of these, the distribution areas of 9 species are expanding towards northern Europe and / or Asia, an effect that may relate to the current climate change process. On the contrary, in the current review 4 species cited in the study conducted in the mid-twentieth century have not been detected.

Los sistemas fluviales mediterráneos, caracterizados por precipitaciones irregulares y de gran intensidad, constituyen ambientes de extremada vulnerabilidad. Estos sistemas, ya de por si alterados, se ven afectados por cambios morfológicos generados por actuaciones de origen antrópico, que han ocasionado en las últimas décadas numerosos y graves efectos ambientales. Una evidente muestra de ello se produce en el río Chico, que se ha visto sometido a una intensa alteración hidrológica y morfológica. La construcción de diques y escolleras han sido las obras más utilizadas, aunque no han sido siempre efectivas, generando en muchos casos variaciones en los flujos sedimentarios y en los procesos de erosión. Por el contrario, las obras de menor tamaño presentan una mejor integración en el lecho, actuando mejor y no han provocado grandes alteraciones locales. La ausencia o disminución de estas actuaciones en el cauce dispondría de un mayor espacio fluvial, garantizando la recuperación de sus valores naturales. The Mediterranean fluvial systems, characterised by irregular and high intensity rainfall, are extremely vulnerable environments. These natural systems are altered by human activities, causing morphological adjustments and numerous, serious environmental problems in recent decades. A clear example of this is the river Chico, which has been submitted to an intense alteration, both hydrologic and morphologic. Dams and ripraps have been the constructions used most, although they have not always been effective, in many cases generating changes in the sedimentary flows and in the processes of erosion. On the contrary, the smaller-scale works carried out present a better integration in the riverbed, have performed well and have not provoked big local alterations. The absence or decrease of these works in the riverbed would yield a greater fluvial space, guaranteeing the recovery of the natural values. Fundación Instituto Euromediterráneo de Hidrotecnia, Consejo Europeo y Comunidad Autónoma de la Región de Murcia PI/13