Synthesis and characterization of QD-3: the first organically templated aluminoborate with 11-, 12-, and 14-ring intersecting channels

QD-3, a novel aluminoborate (TETA) 2[Al 2B 10 O 20].0.25H 2O (TETA = triethylenetetramine), has been solvothermally synthesized and characterized by IR, thermogravimetric analysis, power X-ray diffraction, elemental analysis, and single-crystal X-ray diffraction. This compound crystallizes in the orthorhombic system, space group Pna2 1 (No. 33), a = 25.9174(2) A, b = 7.4028(5) A, c = 17.013(4) A, V = 3264.2(2) A (3), and Z = 4. Its structure consists of AlO 4 tetrahedra and B 5O 10 clusters, which are interconnected and form a three-dimensional framework with large 11-, 12-, and 14-ring channels.     

Synthesis of a new zeolite structure ITQ-24, with intersecting 10- and 12-membered ring pores

A new 10- and 12-membered ring zeolite, named ITQ-24, has been synthesized, and its structure has been solved. It has been found that this zeolite structure is topologically identical to that proposed for the hypothetical polymorph C of the SSZ-33/SSZ-26/CIT-1 family. This new zeolite has been achieved by using a rational approach of introducing Ge in the framework that has a directing effect toward zeolite structures with double-four-membered rings as secondary building units. Notoriously, active catalytic centers, such as Ti and Al, have been incorporated into this new zeolite, demonstrating that it is catalytically active for alkylation of aromatics.     

P-derived organic cations as structure-directing agents: synthesis of a high-silica zeolite (ITQ-27) with a two-dimensional 12-ring channel system

Recently, efforts have been made to synthesize large-pore, multidimensional zeolite frameworks as a basis for new catalysts to improve various hydrocarbon conversions. A new aluminosilicate zeolite, ITQ-27, has been prepared using the phosphorus-containing structure-directing agent, dimethyldiphenylphosphonium. Its crystal structure was determined in its calcined form by direct methods (FOCUS) on synchrotron powder diffraction data (lambda = 0.8702 A) after the unit cell and space group were determined from tilt electron diffraction experiments on individual microcrystals. The material crystallizes in space group Fmmm, where a = 27.7508(5) A, b = 25.2969(7) A, and c = 13.7923(4) A. The final model, refined by Rietveld methods, comprises seven unique T-sites forming a framework with straight 12-MR channels that are connected by 14-MR openings between them. (Corresponding 12-ring pore dimension is 6.94 A x 6.20 A.) Since access from one 14-MR opening to the next is through the 12-MR channel, the structure is best described as a two-dimensional, 12-MR framework.     

The synthesis,characterization, and structure solution of SSZ-58: a novel two-dimensional 10-ring pore zeolite with previously unseen double 5-ring subunits

The synthesis, structure solution, and characterization of the novel zeolite SSZ-58 are described. SSZ-58 was synthesized under hydrothermal conditions using 1-butyl-1-cyclooctylpyrrolidinium cation as a structure-directing agent. The framework topology of SSZ-58 was determined with the FOCUS Fourier recycling method. SSZ-58 possesses 12 tetrahedral atoms in the asymmetric unit of its highest topological symmetry, and to date it is the most complex zeolite structure solved from powder data. Rietveld refinement of synchrotron powder X-ray diffraction data in space group Pmma confirmed the proposed model. SSZ-58 contains layers of atoms that are linked together by double five-membered rings (D5R), or 5(2)4(5) subunits, that have not been observed before in any zeolite or zeotype structures. SSZ-58 possesses a two-dimensional channel system consisting of 10-membered ring pores that intersect to form large cavities circumscribed by 12- and 16-membered ring pores.     

MCuB7O12.nH2O (M = Na, K ): a new copper borate with 14-ring channels

The title compounds, which were synthesized in boric acid flux under mild conditions (493 K), contain a 14-member ring borate framework consisting of octahedral (CuO6), tetrahedral (BO4) and triangular (BO3) units.     

Synthesis design and structure of a multipore zeolite with interconnected 12- and 10-MR channels

A new molecular sieve, ITQ-38, containing interconnected large and medium pores in its structure has been synthesized. The rational combination of dicationic piperidine-derivative molecules as organic structure directing agents (OSDAs) with germanium and boron atoms in alkaline media has allowed the synthesis of ITQ-38 zeolite. High-resolution transmission electron microscopy (HRTEM) has been used to elucidate the framework topology of ITQ-38, revealing the presence of domains of perfect ITQ-38 crystals as well as very small areas containing nanosized ITQ-38/ITQ-22 intergrowths. The structure of ITQ-38 is highly related to ITQ-22 and the recently described polymorph C of ITQ-39 zeolite. It shares a common building layer with ITQ-22 and contains the same building unit as the polymorph C of ITQ-39. All three structures present similar framework density, 16.1 T atoms/1000 ?(3).     

Synthesis and Structure of KBGe2O6: the first chiral zeotype borogermanate with 7-ring channels

Among the known zeolite topologies, odd rings are rare with the exception of 5-ring. We report here the hydrothermal synthesis and structural characterization of a novel compound, KBGe(2)O(6), the first germanate-based zeotype material with 7-ring channels. It crystallized in the orthorhombic system, space group P2(1)2(1)2(1) (No. 19), a = 4.8037(3) A, b = 10.2063(7) A, c = 10.7402(10) A, V = 526.57(5) A(3), Z = 3. The framework topology of this compound is previous unknown with the vertex symbol 4.6.4.6.6.7(2)(vertex1), 4.6.4.6.6.7(2)(vertex2), and 6.6.6.6.6(2) x 7(2)(vertex3). It is worth noting that the structure of the compound is chiral containing helices condensed from GeO(4) tetrahedra, which arrange around 2(1) screw axes. Furthermore, the K(+) ions within the channels are mobile and can be partially ion-exchanged with Na(+) at room temperature.     

|(C4NH12)4|[M4Al12P16O64] (M = Co, Zn): new heteroatom-containing aluminophosphate molecular sieves with two intersecting 8-ring channels

Two novel heteroatom-containing aluminophosphate molecular sieves, |(C(4)NH(12))(4)|[M(4)Al(12)P(16)O(64)] (denoted MAPO-CJ69, M = Co and Zn), have been solvothermally synthesized using diethylamine as the structure-directing agent. The framework of MAPO-CJ69 exhibits a new zeolite topology which is constructed by strict alternation of metal-centered (Al/M)O(4) tetrahedra and PO(4) tetrahedra to form a three-dimensional anionic [M(4)Al(12)(PO(4))(16)](4-) framework. The structure contains two intersecting 8-ring channels along the [010] and [001] directions, and the protonated diethylamine cations reside in the 8-ring channels to achieve charge neutrality. The structure of MAPO-CJ69 is composed of the 4-4- secondary building unit (SBU), which has been found in some known zeolites, such as AFR, SFO, ZON, OWE, etc. The structural relationships between these zeolites have been discussed.     

A germanium zeotype with a three-dimensional net of interconnected 14-, 12- and 12-ring channels. Ge13O26(OH)4[C6N2H16]2(H2O)1.5

Ge(13)O(26)(OH)(4)[C(6)N(2)H(16)](2)(H(2)O)(1.5) is a novel germanium zeotype built up from a new type of SBU; the SBU-13 is formed from polyhedra distributed in three shells. Its open 3D framework has a three-dimensional system of intersecting channels, where the 14-ring channels are lined with OH(-) anions.     

ITQ-16, a new zeolite family of the beta group with different proportions of polymorphs A,B and C

ITQ-16 is a new zeolite family formed by polymorphs A, B and C of the beta intergrowth in which the proportion of polymorph C can be controlled by changing the organic structure directing agent and/or by changing the Ge content of the synthesis gel; ITQ-16 can be synthesised either in fluoride or fluoride-free medium and Al can be introduced in the framework giving a material with very strong Br?nsted acidity.     

Synthesis, structure solution, characterization, and catalytic properties of TNU-10: a high-silica zeolite with the STI topology

A high-silica zeolite (Si/Al = 7.1) with the STI framework topology, denoted TNU-10, has been synthesized in the presence of 1,4-bis(N-methylpyrrolidinium)butane and Na(+) cations as structure-directing agents, and its structure in the proton form has been refined against laboratory powder X-ray data in space group Fmmm (a = 13.533(1) A, b = 17.925(2) A, c = 17.651(2) A). The space group symmetry is supported by electron diffraction and energy minimization studies. The as-made and proton form of TNU-10 are extensively characterized by elemental and thermal analyses, scanning electron microscopy, N(2) adsorption, multinuclear solid-state NMR, IR, and temperature-programmed desorption of ammonia, and the location of the organic structure-directing agent in the channel system is determined by molecular modeling. The catalytic properties of H-TNU-10 and Co-TNU-10 are evaluated for the skeletal isomerization of 1-butene to isobutene and the selective reduction of NO with methane, respectively. When compared to H-ferrierite, a low selectivity to isobutene is observed for H-TNU-10. However, it is found that Co-TNU-10 exhibits a maximum NO conversion of 93% at 823 K under conditions of high concentrations of methane (16,000 ppm) and water vapor (10%) and in the presence of 2.6% O(2), which is considerable higher than even the value (74%) obtained from Co-ferrierite, known as the best catalyst for this reaction, under the identical conditions.     

[Ni(C6N2H14)2][Zn4(H2O)(HPO3)5]: A new open-framework zinc phosphite with intersecting 8-, 12- and 16-ring channels

A new three-dimensional (3-D) zinc phosphite with Zn/P ratio of 4/5, [Ni(C₆N₂H₁₄)₂][Zn₄(H₂O)(HPO₃)₅] (1), has been prepared by using self-assembled nickel complexes as the structure-directing agents. Its structure is built up from strict alternation of ZnO₄ tetrahedra and HPO₃ pseudo-pyramids, resulting in an open framework with multi-directional intersecting 8-, 12- and 16-ring channels. The unique nickel complexes Ni(DACH)₂ (DACH=1,2-diaminocyclohexane) only involving the cis-DACH acting as ligands are self-assembled under hydrothermal conditions, and act as the structure-directing agents (SDAs) to direct the formation of compound 1. Nickel complexes reside in the channels in a manner that the hydrophobic ends of the cis-DACH molecules exclusively protrude into the 16-ring pores and the amino groups closely interact with the charged inorganic framework through weak H-bonds. The interesting arrangements of nickel complexes imply a feasible approach to the design and synthesis of extra-large pore materials.     

Selective sulfoxidation of thioethers and thioaryl boranes with nitrate, promoted by a molybdenum-copper catalytic system

The catalytic reduction of nitrate by molybdo-enzymes plays a central role in the global biological cycle of nitrogen. However, the use of nitrates as oxidants in synthetic organic chemistry is very limited and typically requires very strong acidic and other extreme reaction conditions. We have developed a highly chemoselective and efficient catalytic process for the sulfoxidation of thioethers and arylthioethers containing boronic acid or boronic ester functional groups, using nitrate salts as oxidants. This homogeneous catalytic reaction was carried out in acetonitrile, where the MoO(2)Cl(2)(OPPh(3))(2) complex 1 or a mixture of complex 1 with Cu(NO(3))(2) were used as catalysts. We examined the reaction mechanism using (1)H, (15)N, and (31)P NMR techniques and (18)O-labeled sodium nitrate (NaN(18)O(3)) and show that the thioethers are oxidized by nitrate, generating nitrite. Our work adds to the existing chemical transformations available for organoboron compounds, providing straightforward accessibility to a variety of new substrates that could be suitable for Suzuki cross-coupling chemistry.     

Contribution to the study of carbon and nitrogen determination by activation,using the nuclear reactions12C(α, n)15O and14N(d,n)15O

The carbon and nitrogen activation curves were determined for the nuclear reactions¹²C(α, n)¹⁵O and¹⁴N(d, n)¹⁵O, within the limits of the following maximum energies: 40 MeV for α-particles, and 21 MeV for deuterons. Inferences are made concerning the potential possibilities of these activation methods, from the sensitivity aspects, for the determination of carbon and nitrogen, with reference to the problem of the main interferences which have also been studied experimentally. The chemical separation process used to isolate¹⁵O after irradiation is described. Concrete examples of carbon and nitrogen determinations by these methods are given.     

GeB4O9 x H2en: an organically templated borogermanate with large 12-ring channels built by B4O9 polyanions and GeO4 units: host-guest symmetry and charge matching in triangular-tetrahedral frameworks

A new borogermanate open-framework, FJ-18, with intersecting 12-/8-, 9-, and 9-ring channels in multidimensions was synthesized by using an organic diamine as structure-directing agent (SDA). X-ray diffraction showed that its structure is constructed by flexible connection of strictly alternate B(4)O(9) clusters (with fictitious tetrahedral geometry) and GeO(4) tetrahedra to form a zeotype framework with the CrB(4) topology. The topology and structural relations between FJ-18 and FJ-16, a known borogermanate based on the linkage of B(4)O(9) clusters and GeO(4) units, are described in detail. Different guest SDAs can, by means of their shape, size, and charge, directly influence the structure of the host framework, and the origin of these phenomena can be attributed to fundamental parameters such as host-guest symmetry and charge matching through H-bonding interactions, the concept of which has for the first time been extended to tetrahedral-triangular frameworks. This result is a part of our ongoing work aimed at making new large-pore materials constructed from B-O polyanions and Ge-O cluster units.     

Host (nanocavity of zeolite-Y)/guest (12- and 14-membered azamacrocyclic Ni(II) complexes) nanocatalyst: synthesis, characterization and catalytic oxidation of cyclohexene with molecular oxygen

Ni(II) complexes of [12]aneN₄: 1,4,7,10-tetraazacyclododecane-2,3,8,9-tetraone; [14]aneN₄: 1,4,8,11-tetraazacyclotetradecane-2,3,9,10-tetraone; Bzo₂[12]aneN₄: dibenzo-1,4,7,10-tetraazacyclododecane-2,3,8,9-tetraone and Bzo₂[14]aneN₄: dibenzo-1,4,8,11-tetraazacyclotetradecane-2,3,9,10-tetraone have been encapsulated in the nanopores of zeolite-Y by a two-step process in the liquid phase: (i) adsorption of [bis(diamine)nickel(II)]; [Ni(N–N)₂]–NaY; in the supercages of the zeolite, and (ii) in situ condensation of the nickel(II) precursor complex with diethyloxalate. The new host-guest nanocatalyst (HGN) were characterized by several techniques: chemical analysis and spectroscopic methods (FT-IR, UV/Vis, XRD, BET, DRS) and then were used for oxidation of cyclohexene with molecular oxygen.     

Investigation of the alkylation of nitroazoles with α-haloketones by13C,15N,and14N NMR

General methods have been worked out for the alkylation of nitroazoles with bromoacetone, bromoacetophenone, and diazoacetone in homogeneous media and by phase-transfer catalysis. The structures of the N-acetonylazoles were established by¹³C,¹⁵N, and¹⁴N high-resolution NMR spectroscopy.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1827–1837, August, 1990.