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The solubility of four copper ligand systems in supercritical (SC) CO2 was studied. Three of the ligand systems studied were commercial ligands, while the last one was a new Schiff base reduced macrocyclic ligand. The three commercial ligands were ethylenediaminetetraacetic acid (EDTA), diisooctylphosphinic acid (DiOPA), and the anion-exchanger Aliquat 336 (methyltrioctylammonium chloride). The Schiff base reduced macrocyclic ligand was 3,6,9,12-tetraaza-4(1,2),11(1,2)-dibenzena-1(1,3)-pyridinacyclotridecaphane (TeDiPyDeca), which forms a very stable 1 + 1 copper complex (Keq = 2.42 × 106). This article presents the synthesis, Fourier transform infrared spectroscopy (FT-IR) studies, and crystal structure of the new copper complex Cu(TeDiPyDeca) as well as experimental data of solubility fitting with a Peng Robinson equation and van der Waals mixing rules. The molar volume of the solid (Vs), the vapor pressure (Pvap), and the binary interaction coefficient (k ij ) of the four metal complexes were found. Th...

In the title salt, C16H24N42+·2NO3−, both the cation and anion are placed in general positions, although the cation displays non-crystallographic inversion symmetry, with the aliphatic chain extended in an all-transconformation. The benzene rings are almost parallel, with a dihedral angle between their mean planes of 3.3 (6)°. The nitrate ions are placed in the vicinity of the protonated amine groups, forming efficient N—H...O inter-ion hydrogen bonds. Each nitrate ion in the asymmetric unit bridges two symmetry-related cations, forming anR44(18) ring, a common motif in organic ammonium nitrate salts. This results in the formation of chains along [010] with alternating cations and anions. The neutral amine groups are involved in slightly weaker N—H...O hydrogen bonds with the nitrate O atoms, and there are also a number of C—H...O hydrogen bonds present. The resulting supramolecular structure is based on a two-dimensional network extending in theabplane.

The title compound, C(16)H(26)N(4) (4+)·4Cl(-), is based on a fully protonated tetra-amine. In the cation, both benzene rings are connected by an all-trans chain, and the rings are almost parallel, with an angle between the mean planes of 8.34 (12)°. The benzene rings are arranged in such a way that the NH(3) (+) substituents are oriented cis with respect to the central chain. This arrangement is a consequence of multiple N-H⋯Cl hydrogen bonds, involving all N-H groups in the cation and the four independent Cl(-) anions. These contacts have strengths ranging from weak to strong (based on H⋯Cl separations), and generate a complex three-dimensional crystal structure with no preferential crystallographic orientation for the contacts.

The title Schiff base, C27H33N7, is a tripodal amine displaying C3 symmetry, with the central tertiary N atom lying on the threefold crystallographic axis. The N—CH2—CH2—N conformation of the pendant arms is gauche [torsion angle = 76.1 (3)°], which results in a claw-like molecule, with the terminal aniline groups wrapped around the symmetry axis. The lone pair of the apical N atom is clearly oriented inwards towards the cavity, and should thus be chemically inactive. The amine NH2 substituents lie in the plane of the benzene ring to which they are bonded. With such an arrangement, one amine H atom forms an S(6) motif through a weak N—H...N hydrogen bond with the imine N atom, while the other is engaged in an intermolecular N—H...π contact involving the benzene ring of a neighbouring molecule related by inversion. The benzene rings also participate in an intramolecular C—H...π contact of similar strength. In the crystal structure, molecules are separated by empty voids (ca 5% of the crystal volume), although the crystal seems to be unsolvated.

The title compound, C(16)H(26)N(4) (4+)·2.5ClO(4) (-)·1.5NO(3) (-), is an organic salt in which the cation is a fully protonated tetra-mine. The cation lies on an inversion center and, as a consequence, both benzene rings are parallel. The central chain is found in an all-trans arrangement, a conformation different from that observed in the crystal structure of the non-protonated mol-ecule. The charges are balanced by a mixture of nitrate and perchlorate ions. One site is occupied by an ordered perchlorate ion, while the other contains both nitrate and perchlorate ions, with occupancies of 0.75 and 0.25, respectively. In the crystal, the NH(2) (+) groups of the cation form N-H⋯O hydrogen bonds with the anions. The NH(3) (+) groups also behave as donor groups, allowing the building of chains along [100], alternating cations and disordered anions being connected via N-H⋯O hydrogen bonds.

Sin resumen

En el presente trabajo se llevó a cabo la degradación mediante aminólisis de polietilentereftalato (PET) obtenido de botellas desechables, con el producto obtenido se realizó la remoción de dodecilbenceno sulfonato de sodio (SDBS) presente como contaminante en agua. En el proceso de degradación se mezcló el PET con etilendiamina (EDA) y se calentó a 116 ºC durante 90 minutos en presencia de estearato de zinc como catalizador, el producto obtenido (oligómero) se caracterizó mediante análisis elemental (AE), espectroscopía de infrarrojo (FTIR) y calorimetría diferencial de barrido (DSC). La influencia del pH y el tiempo de contacto fue estudiado en la remoción de SDBS. Mediante la técnica de sustancias activas al azul de metileno (SAAM) se determinó la cantidad de surfactante que fue removido del agua por el oligómero. Se logró remover el tensoactivo hasta 90 % con tiempo de contacto de una hora y pH 3; así mismo, se determinó la capacidad máxima de adsorción del oligómero, la cual es de188 mg/g.

There are twenty four elements known to be necessary for human life, seven of which are transition metals. These seven elements; V, Cr, Mn, Fe, Co, Cu, and Zn have an important role in living systems due to their ability to form complexes with diverse donor groups present in biological systems. [Co(salen)] has been previously studied as a model compound for oxygen transport. In this work other metallic complexes, Ni(II), Zn(II), Cu(II) and Fe(II) with N,N'-bis(salicylaldehyde)ethylenediamine (salen-H2) were synthesized. The active form of each complex was obtained by reaction with dimethylsulfoxide. The ability of these metallic complexes to act as O2 carriers was determined. From the results, the complexes of the Co(II), Fe(II) and Cu(II) with salen are able to transport oxygen with an ordering of Co(II) > Fe(II) > Cu(II) regarding the capacity to carry O2. We used the PM7 semiempirical hamiltonian to study the complexes of salen with Co(II), Cu(II), Fe(II) and Ni(II) and their potential as oxygen carriers. We performed full geometry optimizations in the gas phase for each complex, its active form with DMSO as ligand, and with dioxygen complexed with the active form. We discuss energetic features associated with the binding of dioxygen to the complexes.

The title mol-ecule, C(17)H(16)N(4), is a bis-indazole crystallized in the rare 2H-tautomeric form. Indazole heterocycles are connected by a propane C(3) chain, and the mol-ecule is placed on a general position, in contrast to the analogous compound with a central C(2) ethane bridge, which was previously found to be placed on an inversion center in the same space group. In the title mol-ecule, indazole rings make a dihedral angle of 60.11 (7)°, and the bridging alkyl chain displays a trans conformation, resulting in a W-shaped mol-ecule. In the crystal, mol-ecules inter-act weakly through π-π contacts between inversion-related pyrazole rings, with a centroid-centroid separation of 3.746 (2) Å.

Se evaluó el rendimiento cuántico del complejo diaqua-[tris(nitrato)]-bis[2,6-bis(2-formilfenoximetil)piridina]neodimio(III) mediante el método Petoud [1] ( = 0.56), para esto se prepararon disoluciones del complejo del orden de 10-5 M, donde se muestra que la propiedad fotoluminiscente es inversamente proporcional a la concentración del compuesto en la disolución. Para llevar a cabo lo anterior, primero se midió el espectro de emisión del complejo donde se observó que la señal en 864 nm es la de máxima intensidad, resultando mayor que la de la sal de partida. El complejo se sintetizó previamente por reacción directa mezclando disoluciones de la sal Nd(NO3)3.6H2O y L en relación 1:2, y se caracterizó por análisis elemental (AE), espectroscopía de infrarrojo (IR) y mediante difracción de rayos X de monocristal se obtuvo su estructura cristalina [2]. Los resultados obtenidos en este trabajo servirán de base para proponerse en la preparación de nuevos materiales del tipo láseres o fibras ópticas ya que el compuesto tiene la particularidad de emitir tanto en el visible como en el infrarrojo cercano.

La importancia de los derivados del 2H-indazol es debida a la actividad biológica que han presentado, lo que ha permitido aplicarlos en la industria farmacéutica, en el sector agrícola entre otros. En este trabajo, primeramente se estudió la influencia de la concentración del N,N'-bis(2-nitrobencil)-1,2-etanodiamina [Pi] y diferentes cantidades tanto de agente reductor como de catalizador para favorecer la formación del 2,2'-(etano-1,2-diil)bis(2H-indazol) [L,], utilizando un diseño de experimentos 23• Posteriormente, se sintetizó un nuevo derivado del 2H-indazol, el 2,2'-(propano-1,3-diil)bis(2H-indazol) [L,], mediante la aplicación de las mejores condiciones obtenidas en el diseño de experimentos, así como, mediante la modificación del tiempo de adición del agente reductor. Las condiciones de reacción más favorable resultaron ser: baja concentración de P,, baja cantidad de catalizador y alta cantidad de agente reductor. Con respecto a la síntesis de L,, se estableció que el tiempo de adición del agente reductor es un factor determinante, encontrando que el incremento del mismo favorece su obtención.

The synthesis and characterization of cis- and trans- 3-oxo-3-phenyl-2,2,5-trimethyl-1,3-oxaphosphorinanes (7a and 7b) and their corresponding tetrafluoroborate salts (3a and 3b) , heterocyclic organophosphorus compounds not previously reported in the literature, was accomplished. They were fully characterized by 1H, 13C and 31PNMR. It was established the relative configuration of these compounds on the basis of an X-ray diffraction study of oxide 7a.

The asymmetric unit of the title compound C11H16N,05 , contains one molecule of the compound (L3) (1,3-bis(2-nitrobenzylideneamino )propan-2-ol). The molecule shows a chiral C atom but the absolute structure was not possible to be determined by X-ray diffraction. The molecule shows intermolecular hydrogen bonding involving the hydroxy group and an imine nitrogen atom of a symmetry related molecule. The molecular distribution shows weak interactions between oxygen atoms of the nitro groups and two different C-H groups of benzene rings. The extended weak H bond formation, using the N02 groups, probably gives a more stable crystal structure. The molecule represents a precursor of a polyaza macrocylic ligands.

En este artículo se describe la tecnología para la implementación de la gestión integrada de capital humano (TEIGICH) en hospitales, la cual consta de cinco etapas, partiendo de caracterizar al hospital, identificar al servicio que se estudie, determinar las oportunidades de mejora, rediseñar los subprocesos de la Gestión de Capital Humano (GCH) y elaborar el Dossier de la Gestión Integrada de Capital Humano (GICH), controlando el proceso y dándole seguimiento. Se usaron técnicas y métodos como: recopilación bibliográfica, encuestas, entrevistas, el método general para resolver problemas, diagrama Causa-Efecto, mapas de proceso, listas de chequeo, revisión y análisis de documentos y herramientas informáticas. Se concluyó que el diseño de la tecnología deberá contribuir a la aplicación de las NC 3000-3002: 2007 del Sistema de GICH en hospitales.