Tetra

In this study, the novel peripherally tetra 4-isopropylbenzyloxy substituted metal-free (4) zinc(II) (5) and oxo-titanium(IV) (6) phthalocyanine complexes were synthesized. Furthermore, the axially 4-isopropylbenzyloxy silicon(IV) phthalocyanine derivative (7) was also synthesized. These novel compounds were characterized by different spectroscopic methods such as FT-IR, 1 H-NMR, UV-vis and mass. The spectroscopic, photophysical and photochemical properties including electronic absorption, steady state fluorescence, singlet oxygen generation and photostability in toluene were studied.

In this study, the novel peripherally tetra 4-isopropylbenzyloxy substituted metal-free (4) zinc(II) (5) and oxo-titanium(IV) (6) phthalocyanine complexes were synthesized. Furthermore, the axially 4-isopropylbenzyloxy silicon(IV) phthalocyanine derivative (7) was also synthesized. These novel compounds were characterized by different spectroscopic methods such as FT-IR, 1 H-NMR, UV-vis and mass. The spectroscopic, photophysical and photochemical properties including electronic absorption, steady state fluorescence, singlet oxygen generation and photostability in toluene were studied.

A series of tridentate ligands N,N-bis-[(di-substituted-1-pyrazolyl)methyl]arylamines 2-3a,b and benzylamine 4a,b, tetradentate N,N 0-bis-[(di-substituted-1-pyrazolyl)methyl]para-phenylenediamines 7a,b and hexadentate N,N,N 0 ,N 0-tetra-[(di-substituted-1-pyrazolyl)methyl]para-phenylenediamines 8a,b has been prepared in good yield by condensation of arylamines, benzylamine or paraphenylenediamine with N-hydroxymethyl disubstituted pyrazoles 1a,b. The synthesis and characterisation of these various polydentate ligands are described.

The title compound, molecular formula C30H40N10, crystallizes and exhibits a cisoidal conformation around a central p-phenylenediamine ring suggesting that this bis-tripodal ligand is highly flexible and could be accommodated by many and original metal coordinations. All four five-membered pyrazole rings are identical. The molecule presents an inversion centre that coincides with the phenyl ring centre: pyrazole rings are two-by-two equivalent. The electrostatic spatial intramolecular repulsion between N4 and N5 is probably responsible for this general arrangement. These data emphasize the basic character of nitrogens N4 and N5.

Several improved approaches for the preparation of tetra-O-benzyl-D-glucopyranosyl bromide and tetra-O-pivaloyl-D-glucopyranosyl bromide are discussed. The importance of these compounds, which are useful glycosyl donors, was demonstrated by successful preparation of cholesteryl glucopyranosides in an almost neutral medium without the formation of orthoesters. In addition, accurate 1 H and 13 C NMR resonance assignments of the synthesized cholesteryl glycosides were performed by 2D NMR spectroscopy.

Capítulo IV. RESULTADOS Y DISCUSIÓN. 4.1. Proceso de separación Aluminio-polímero. 4.1.1. Desprendimiento del cartón. 4.1.2. Molienda. 4.1.3. Separación por medio de un calentamiento. 4.1.4. Filtración del polímero con saturación de aceite. 4.1.5. Lavado del polímero. 4.2. Cantidad final de LDPE. 4.3. Porcentaje total de aceite. 4.4. Porcentaje final de cloroformo recuperado. Capítulo V. CONCLUSIONES. Capítulo VI. RECOMENDACIONES. Capítulo VII. ANEXOS. Anexo I. Propiedades moleculares básicas del LDPE. Anexo II. Parámetros que influyen en la composición y rendimiento de los productos químicos resultantes de un proceso de pirolisis. GLOSARIO. REFERENCIAS Relación de tablas PÁG. No.1 Envases multicapa vendidos por Tetra Pak [26]. No.2 Propiedades mecánicas del LDPE [37]. No.3 Propiedades físicas del LDPE [42,43]. Np.4 Propiedades químicas del LDPE [42, 43]. No.5 Propiedades eléctricas del LDPE [42, 43]. No.6 Ventajas y desventajas de los procesos de reciclaje químico para el LDPE [50]. No.7 Cantidades de material utilizado para cada uno de los lavados de polímero. No.8 Cantidades de LDPE obtenidos por cada muestra después de ser lavado con cloroformo. No.9 Cantidades totales de LDPE recuperado y aceite presente en cada muestra. No.10 Cantidad total de aceite recuperado en las etapas del proceso (Calentamiento y lavado de LDPE). No.11 Cantidad total de cloroformo recuperado por cada muestra.

A new 2,3,4,6-tetra-O-(3-nitropropanoyl)-O-β-D-glucopyranoside anomer was isolated from the roots of Heteropteris aphrodisiaca and characterized by spectroscopic methods. Activity against Staphylococcus aureus, Bacillus subtilis, Candida albicans, C. parapsilosis, C. krusei, and C. tropicalis was demonstrated. RESUMEN. "2,3,4,6,-Tetra-O-(3-nitropropanoil)-O-β-D-glucopiranósido, Un Nuevo Antimicrobiano de las Raíces de Heteropteris aphrodisiaca". Un nuevo 2,3,4,6-tetra-O-(3-nitropropanoila)-O-β-D-glucopiranósido anomérico fue aislado de las raíces de Heteropteris aphrodisiaca y su estructura determinada por métodos espectroscópicos. Su actividad frente a los microorganismos Staphylococcus aureus, Bacillus subtilis, Candida albicans, C. parapsilosis, C. krusei y C. tropicalis fue demostrada.

Tesselation of new porphyrin-based network motifs was demonstrated in crystals by incorporation of the diaminotriazine functions in the molecular building blocks. The title compound was synthesized and successfully applied in the construction of a uniquely structured solid which consists of flat multiporphyrin networks with very large voids, 2.2 Â 2.2 nm 2. These assemblies mutually interpenetrate each other, yielding a spectacular concatenated arrangement sustained in three dimensions by cooperative hydrogen bonding. The resulting multiporphyrin architecture resembles a molecular-sieve material, having 0.6 nm wide channels which propagate through the crystal and are accessible to other molecules.

Tetra alkyl ammonium bromates are prepared by a simple procedure and used for the oxidative regeneration of the parent carbonyl compound from their semicarbazones. Reaction conditions are simple and the deprotection gives satisfactory yield of the carbonyl compound.

Tetra-auricupride, ideally AuCu, represents the only species showing the coexistence of Au with an elevated level of Pt, as in the case of a detrital grain studied structurally for the first time, from an ophiolite-associated placer at Bolshoy Khailyk, western Sayans, Russia. We infer that tetra-auricupride can incorporate as much as~30 mol. % of a "PtCu" component, apparently without significant modification of the unit cell. The unit-cell parameters of platiniferous tetra-auricupride are: a 2.790(1) Å, c 3.641(4) Å, with c/a = 1.305, which are close to those reported for ordered AuCu(I) in the system Au-Cu, and close also to the cell parameters of tetraferroplatinum (PtFe), which both appear to crystallize in the same space group, P4/mmm. These intermetallic compounds and natural alloys are thus isostructural. The closeness of their structures presumably allows Pt to replace Au atoms so readily. The high extent of Cu + Au enrichment is considered to be a reflection of geochemical evolution and buildup in levels of the incompatible Cu and Au with subordinate Pt in a remaining volume of melt at low levels of f O 2 and f S 2 in the system.

Functionalised tetra-ortho-methoxyazobenzenes have been prepared in a two-step approach based on palladium-catalysed C-H ortho bromination of azobenzenes, followed by copper-catalysed methoxylation. The method has shown a broad tolerance to different functional groups that could not be incorporated by previous strategies. With this two-step transition metal-catalysed strategy, we achieved overall yields that range from good to excellent and enable the exploitation of these highly coveted photoswitches. The superior robustness of this scaffold for Solid Phase Synthesis applications when compared to its chlorinated counterpart has been demonstrated after extensive treatments with piperidine while bound to a RinkAmide ChemMatrix resin, showcasing their potential for use in the synthesis of red-light-operated peptides.

Oxide-based electrocatalysts were investigated as non-platinum cathodes for the oxygen reduction reaction (ORR). Recently, we found that titanium oxide-based compounds produced from oxy-titanium tetra-pyrazino-porphyrazine via oxidation under low oxygen partial pressure exhibited high ORR activity [T. Hayashi et al., ECS Trans., 64(3), 247 (2014)]. However, the mechanism by which the ORR proceeds in the presence of titanium oxide-based catalysts has not yet been analyzed in detail. In this study, the ORR mechanism was investigated based on the Damjanovic model by using a rotating ring disk electrode. The titanium oxide-based catalysts showed high reactivity in the four electron reduction of O 2 .

The title compound, sodium trimagnesium bis(hydrogen phosphate) phosphate, was obtained under hydrothermal conditions. In the crystal, two types of [MgO 6 ] octahedra, one with point group symmetry 2, share edges to build chains extending parallel to [101]. These chains are linked together by two kinds of phosphate tetrahedra, HPO 4 and PO 4 , the latter with point group symmetry 2. The three-dimensional framework delimits two different types of channels extending along [001]. One channel hosts the Na + cations (site symmetry 2) surrounded by eight O atoms, with Na-O bond lengths varying between 2.2974 (13) and 2.922 (2) Å. The OH group of the HPO 4 tetrahedron points into the other type of channel and exhibits a strong hydrogen bond to an O atom of the PO 4 tetrahedron on the opposite side.

Electron paramagnetic resonance spectroscopy has been applied to obtain information on the in-plane anisotropy of Cu(II) [ tetrakis-(3,3dimethyl-I-butoxy carbonyl)]phthalocyanine (CuPcBC) molecules deposited as a Langmuir-Blodgett film on a biaxially oriented mylar substrate. We have found that the in-plane distribution of orientations of the film molecules depends on the angle between the axis of preferential order identified in the substrate and the dipping direction. The in-plane orientational anisotropy of the material in the film is mainly due to the ability of the substrate to induce oriented growth of CuPcBC molecules which reflects its surface order.

The asymmetric unit of the title compound, [Li4(C5H3N2O2)4(H2O)4], contains two symmetry-independent LiIions, two symmetry-independent ligands and two symmetry-independent coordinated water molecules. They form a dinuclear unit in which the two LiIions are bridged by two carboxylate O atoms from the two ligands. Two dinuclear units related by an inversion centre form the tetrameric molecule. One of the LiIions shows a distorted tetrahedral coordination geometry, the other a distorted trigonal–bipyramidal environment. The tetramers are held together by hydrogen bonds in which coordinated water molecules act as donors, and the carboxylate O atoms act as acceptors. A hydrogen bond between coordinated water molecule as donor and a ring N atom as acceptor is also observed.

In this study, the ability of J. curcas in the extraction of Lead (Pb) and Copper (Cu) from soils irrigated with municipal waste water was investigated. The seeds of J. curcas were planted in pots containing soil (1kg) obtained from vegetable garden irrigated with municipal waste water. Due to the limited availability of some metals to plants, chelating agents such as ethylene diamine tetra acetic acid (EDTA) was applied to the soil to facilitate the solubilisation and transport of these metals to the plant roots. EDTA (5ml, 0.1mmol) was added on the 10 th , 11 th and 12 th week. In the control, EDTA was not added and all the plants were harvested after 13 weeks of planting. The average number of leaves and shoot heights of the plants were recorded. Pb and Cu contents in the roots and shoots of the plants in EDTA treated soil and control were analyzed using Microwave plasma atomic emission spectrophotometer (MP-AES). The results obtained showed that the application of EDTA increased (P < 0.05) the average number of leaves and shoot heights of J. curcas when compared to control. The results obtained also showed that EDTA increased (P < 0.05) the uptake of metals in the tissues of the plant when compared to control. Phytoextraction ability was assessed in terms of bio concentration factor (BCF) and transfer factor (TF). Based on the TF and BCF values, J. curcas can be used as a good candidate for the removal of Pb and Cu in the soil.

In this study, the ability of J. curcas in the extraction of Lead (Pb) and Copper (Cu) from soils irrigated with municipal waste water was investigated. The seeds of J. curcas were planted in pots containing soil (1kg) obtained from vegetable garden irrigated with municipal waste water. Due to the limited availability of some metals to plants, chelating agents such as ethylene diamine tetra acetic acid (EDTA) was applied to the soil to facilitate the solubilisation and transport of these metals to the plant roots. EDTA (5ml, 0.1mmol) was added on the 10 th , 11 th and 12 th week. In the control, EDTA was not added and all the plants were harvested after 13 weeks of planting. The average number of leaves and shoot heights of the plants were recorded. Pb and Cu contents in the roots and shoots of the plants in EDTA treated soil and control were analyzed using Microwave plasma atomic emission spectrophotometer (MP-AES). The results obtained showed that the application of EDTA increased (P < 0.05) the average number of leaves and shoot heights of J. curcas when compared to control. The results obtained also showed that EDTA increased (P < 0.05) the uptake of metals in the tissues of the plant when compared to control. Phytoextraction ability was assessed in terms of bio concentration factor (BCF) and transfer factor (TF). Based on the TF and BCF values, J. curcas can be used as a good candidate for the removal of Pb and Cu in the soil.

Quantitative structure activity relationship studies have been carried out on cis-hexa and tetra-hydrophthalazinones, a new class of selective PDE-4 inhibitors. The 78 compounds ana lyzed were divided into a training set of 62 and test set of 15 molecules (excluding one compound) each describing a simi lar range of biological activity. Among several 20 and 3D parameters. the molar refractivity, dielectric energy and structural parameters as indicator variables (l J, 1 2 , I]) best describe the variation in PDE-4 inhibitory activity in the training set with high correlation(r=>0.9) of >99% significance. These equations also show a good. test set prediction (r>0.8) and thus may be useful in desi g nin g new potential PDE4 inhibitors.

The tetra-nuclear novel solid complexeswith the general formulae, [M4(H2L- 2H)Clx(H2O)y].zH2O(M=NiII,CoIII; x= 6; y= 8; z = 10 in case ofNiII ; x = 10; y = 8; z = 4 in case of the CoIII complex) and [Co2Ni2(H2L-2H)Cl8(H2O)10], were isolated and characterized by conventional chemical, spectral (IR, UV-Vis., 1H-NMR,Mass), thermal and magnetic measurements. The existence of inter- and intra-molecular hydrogen bonding is confirmed fromthe results of IR and 1H-NMR spectra. Spectral and magnetic data suggest an octahedral geometry around themetal ions in all isolated metal complexes. The low values of magnetic moments suggest the existence of metal-metal interactions. The amounts of solvents inside and/or outside the coordination sphere were determined by gravimetric analysis.

In the title molecule, C24H17ClN4O3S, the central tricyclic moiety is twisted slightly, as indicated by the dihedral angles of 4.86 (5) and 0.97 (6)°, respectively, between the five-membered ring and the C3N3and pyridyl rings. Additionally, the chlorobenzene ring makes a dihedral angle of 65.80 (5)° with the pyridyl ring. Weak C—H...O, C—Cl...N [3.0239 (13) Å] and π–π stacking interactions [inter-centroid distance between thienyl rings = 3.6994 (8) Å, and between thienyl and pyridyl rings = 3.7074 (8) Å] contribute to the molecular packing. The ethyl group in the ester moiety is disordered over two sets of sites, with the major component having an occupancy of 0.567 (11).

In the title compound, C22H23ClN2O2S, the chlorophenyl ring is inclined to the pyridine ring of the isoquinoline ring system by 79.78 (4)°. The cyclohexane ring adopts a flattened boat conformation. In the crystal, dimers form through complementary sets of inversion-related O—H...O and C—H...O hydrogen bonds. These are connected into zigzag chains along the c-axis direction by pairwise C—H...N interactions that also form inversion dimers.

The asymmetric unit of the title salt, 2C17H21N2O2S+·C14H14O7P22−, contains half of a centrosymmetric bis(4-methoxyphenyl)diphosphonate anion and one 2-amino-5-benzyl-3-ethoxycarbonyl-4,5,6,7-tetrahydrothieno[3,2-c]pyridin-5-ium cation. In the anion, the O atoms of the diphosphonate group are disordered over two positions with equal occupancies. In the cation, the ethyl group is disordered over two orientations with a refined occupancy ratio of 0.753 (5):0.247 (5), and the tetrahydropyridinium ring adopts a distorted half-chair conformation. In the crystal, the ions are linked by C—H...O, N—H...O and C—H...S hydrogen bonds into a three-dimensional network.

Preparation and UV/vis, IR, MS,1H NMR, cyclic voltammetry and molecular structures of two new Co(ii) complexes withpara-methoxy-phenyl andpara-chloromeso-porphyrins and 4-cyanopyridine ligand (1–2). Catalytic oxidation data of MB dye using1–2.

The tetra-nuclear novel solid complexeswith the general formulae, [M4(H2L- 2H)Clx(H2O)y].zH2O(M=NiII,CoIII; x= 6; y= 8; z = 10 in case ofNiII ; x = 10; y = 8; z = 4 in case of the CoIII complex) and [Co2Ni2(H2L-2H)Cl8(H2O)10], were isolated and characterized by conventional chemical, spectral (IR, UV-Vis., 1H-NMR,Mass), thermal and magnetic measurements. The existence of inter- and intra-molecular hydrogen bonding is confirmed fromthe results of IR and 1H-NMR spectra. Spectral and magnetic data suggest an octahedral geometry around themetal ions in all isolated metal complexes. The low values of magnetic moments suggest the existence of metal-metal interactions. The amounts of solvents inside and/or outside the coordination sphere were determined by gravimetric analysis.

The preparations of the extremely sterically hindered olefins (12) and (13) are described, and attempts to convert these compounds to other derivatives of tetra-tert-butylethylene (1) are outlined. The preparation of very strained compounds and investigations of therr chemical and spectroscopic properties continue to attract much attention. 1 Of great current interest is the chemistry of very sterically hindered olefrns. 2-10 'Tne ultimate syntnetic goal in this area is the extremely hrndered tetra-tertbutylethylene (1). Another important synthetic target is the less strained 2di-tert-butylmethylenefenchane (2).

Terrestrial Trunked Radio (TETRA) is a digital communication system progressively adopted by Police Forces in Great Britain since 2001. In 2000, the UK Independent Expert Group on Mobile Phones suggested that exposure to TETRA-like signal modulation might have adverse effects on health. The Airwave Health Monitoring Study was established to investigate possible long-term effects of TETRA use on health. This requires estimation of TETRA use among Police Force employees participating in the study. We investigated TETRA usage among 42,112 Police officers and staff. An algorithm was created to link each personal radio user to his/her objective radio usage records for the 26,035 participants with available data. We linked 16,577 personal radio users to their objective radio usage records and compared self-reported usage with data from the TETRA operator for those individuals. For weekly usage, the correlation between self-reported and operator-derived personal radio usage was r=0.69 for ...

A simple and convenient methodology has been developed for the synthesis of novel hexopyranosyl pyrimidine homonucleosides and hexopyranosyl double-headed pyrimidine homonucleosides from the corresponding native sugars, D-glucose and D-mannose. Thus, hexose sugars were converted to 2,6-anhydro-3,4,5,7-tetra-O-benzyl-heptitols and 2,6-anhydro-3,4,5-triO -benzyl-heptitols by recently developed procedure of Khatri et al. Further, mono-and di-hydroxy 2,6-anhydro-heptitols were converted to their corresponding mono-and ditosylated derivatives, which were then translated into hexopyranosyl homonucleosides and double-headed homonucleosides by reaction with uracil and thymine in 40-50 and 27-73% overall yields from tetra-and triO -benzylated anhydro-heptitols.

The electrochemical behavior of tetra-15-crown-substituted phthalocyanine and its copper and cobalt complexes in solution have been studied by voltammetric techniques in wide range of potentials. It is established that the ligand undergoes an irreversible oxidation process, as well as its copper and cobalt complexes. The necessary correlations between electrochemical properties and structures of the ligand and its complexes are proposed.

γ-Alumina nanoparticles (γ-Al 2 O 3 NPs) have been successfully synthesized by electrochemical reduction method. The aqueous solution of tetrapropylammonium bromide was used as an electrolyte cum stabilizer. To prevent spontaneous agglomeration and control nanoparticles size various parameter such as current density, distance between electrodes and concentrations of electrolyte are optimized. γ-Al 2 O 3 NPs thus synthesized were characterized by sophisticated analytical techniques including X-ray diffraction, scanning electron microscopy, energy dispersive spectrophotometer and high-resolution transmission electron microscopy These synthesized γ-Al 2 O 3 NPs were tested used as a catalyst for one pot synthesis of tetraaryl imidazole derivatives from the cyclodehydration and condensation of benzil, aromatic aldehyde, anilines and ammonium acetate under solvent free condition. This method has various advantages like convenient work-up procedure, environmentally benign and less reaction times along with excellent yields. Easy availability, several times recyclability, very simple isolation and eco-friendliness were some attractive features of the nanocrystalline γ-Al 2 O 3 catalyst.