Controlled structural variations in templated uranium sulfates

A series of experiments in the UO(2)(CH(3)CO(2))(2).2H(2)O/H(2)SO(4)/1-(2-aminoethyl)piperazine/H(2)O system were conducted to determine the effects of variation in initial reactant concentrations on the reaction products. Several reaction gels were produced, in which the composition varied from 16:80:4:500 UO(2)(CH(3)CO(2))(2).2H(2)O/H(2)SO(4)/1-(2-aminoethyl)piperazine/H(2)O to 4:92:4:500 UO(2)(CH(3)CO(2))(2).2H(2)O/H(2)SO(4)/1-(2-aminoethyl)piperazine/H(2)O. Single crystals of two new organically templated uranium sulfates, [N(3)C(6)H(18)](2)[(UO(2))(5)(H(2)O)(SO(4))(8)].5H(2)O and [N(3)C(6)H(18)][(UO(2))(2)(H(2)O)(SO(4))(3)(HSO(4))].4.5H(2)O, were isolated. Both compounds exhibit structures in which the inorganic frameworks are two-dimensional and the protonated amines reside between layers, participating in extensive hydrogen bonding. The composition and structure of each compound is dependent on the nature of the starting concentrations. Crystal data: for [N(3)C(6)H(18)](2)[(UO(2))(5)(H(2)O)(SO(4))(8)].5H(2)O, monoclinic, space group P2(1)/n (No. 14), a = 21.5597(3) A, b = 10.2901(2) A, c = 22.8403(3) A, beta = 96.7436(7) degrees, and Z = 4; for [N(3)C(6)H(18)][(UO(2))(2)(H(2)O)(SO(4))(3)(HSO(4))].4.5H(2)O, monoclinic, space group P2(1)/a (No. 14), a = 15.7673(4) A, b = 10.5813(3) A, c = 16.7710(5) A, beta = 99.9216(9) degrees, and Z = 4.     

Synthesis and characterization of uranyl compounds with iminodiacetate and oxydiacetate displaying variable denticity

Eight uranyl compounds containing the dicarboxylate ligands iminodiacetate (IDA) or oxydiacetate (ODA) have been characterized in the solid state. The published polymeric structures for [UO(2)(C(4)H(6)NO(4))(2)] and [UO(2)(C(4)H(4)O(5))](n) have been confirmed, while Ba[UO(2)(C(4)H(5)NO(4))(2)] x 3H(2)O, [(CH(3))(2)NH(CH(2))(2)NH(CH(3))(2)][UO(2)(C(4)H(4)O(5))(2)] [orthorhombic space group Pnma, a = 10.996(5) A, b = 21.42(1) A, c = 8.700(3) A, Z = 4], and [C(2)H(5)NH(2)(CH(2))(2)NH(2)C(2)H(5)][UO(2)(C(4)H(4)O(5))(2)] [monoclinic space group P2(1)/n, a = 6.857(3) A, b = 9.209(5) A, c = 16.410(7) A, beta = 91.69(3), Z = 2] contain monomeric anions. The distance from the uranium atom to the central heteroatom (O or N) in the ligand varies. Crystallographic study shows that U-heteroatom (O/N) distances fall into two groups, one 2.6-2.7 A in length and one 3.1-3.2 A, the latter implying no bonding interaction. By contrast, EXAFS analysis of bulk samples suggests that either a long U-heteroatom (O/N) distance (2.9 A) or a range of distances may be present. Three possible structural types, two symmetric and one asymmetric, are identified on the basis of these results and on solid-state (13)C NMR spectroscopy. The two ligands in the complex can be 1,4,7-tridentate, giving five-membered rings, or 1,7-bidentate, to form an eight-membered ring. (C(4)H(12)N(2))[(UO(2))(2)(C(4)H(5)NO(4))(2)(OH)(2)] x 8H(2)O [monoclinic space group P2(1)/a, a = 7.955(9) A, b = 24.050(8) A, c = 8.223(6) A, beta = 112.24(6), Z = 2], (C(2)H(10)N(2))[(UO(2))(2)(C(4)H(5)NO(4))(2)(OH)(2)] x 4H(2)O, and (C(6)H(13)N(4))(2)[(UO(2))(2)(C(4)H(4)O(5))(2)(OH)(2)] x 2H(2)O [monoclinic space group C2/m, a = 19.024(9) A, b = 7.462(4) A, c = 2.467(6) A, beta = 107.75(4), Z = 4] have a dimeric structure with two capping tridentate ligands and two mu(2)-hydroxo bridges, giving edge-sharing pentagonal bipyramids.     

Methanesulfonates of high-valent metals: syntheses and structural features of MoO2(CH3SO3)2, UO2(CH3SO3)2, ReO3(CH3SO3), VO(CH3SO3)2, and V2O3(CH3SO3)4 and their thermal decomposition under N2 and O2 atmosphere

Oxide methanesulfonates of Mo, U, Re, and V have been prepared by reaction of MoO(3), UO(2)(CH(3)COO)(2)·2H(2)O, Re(2)O(7)(H(2)O)(2), and V(2)O(5) with CH(3)SO(3)H or mixtures thereof with its anhydride. These compounds are the first examples of solvent-free oxide methanesulfonates of these elements. MoO(2)(CH(3)SO(3))(2) (Pbca, a=1487.05(4), b=752.55(2), c=1549.61(5) pm, V=1.73414(9) nm(3), Z=8) contains [MoO(2)] moieties connected by [CH(3)SO(3)] ions to form layers parallel to (100). UO(2)(CH(3)SO(3))(2) (P2(1)/c, a=1320.4(1), b=1014.41(6), c=1533.7(1) pm, β=112.80(1)°, V=1.8937(3) nm(3), Z=8) consists of linear UO(2)(2+) ions coordinated by five [CH(3)SO(3)] ions, forming a layer structure. VO(CH(3)SO(3))(2) (P2(1)/c, a=1136.5(1), b=869.87(7), c=915.5(1) pm, β=113.66(1)°, V=0.8290(2) nm(3), Z=4) contains [VO] units connected by methanesulfonate anions to form corrugated layers parallel to (100). In ReO(3)(CH(3)SO(3)) (P1, a=574.0(1), b=1279.6(3), c=1641.9(3) pm, α=102.08(2), β=96.11(2), γ=99.04(2)°, V=1.1523(4) nm(3), Z=8) a chain structure exhibiting infinite O-[ReO(2)]-O-[ReO(2)]-O chains is formed. Each [ReO(2)]-O-[ReO(2)] unit is coordinated by two bidentate [CH(3)SO(3)] ions. V(2)O(3)(CH(3)SO(3))(4) (I2/a, a=1645.2(3), b=583.1(1), c=1670.2(3) pm, β=102.58(3), V=1.5637(5) pm(3), Z=4) adopts a chain structure, too, but contains discrete [VO]-O-[VO] moieties, each coordinated by two bidentate [CH(3)SO(3)] ligands. Additional methanesulfonate ions connect the [V(2)O(3)] groups along [001]. Thermal decomposition of the compounds was monitored under N(2) and O(2) atmosphere by thermogravimetric/differential thermal analysis and XRD measurements. Under N(2) the decomposition proceeds with reduction of the metal leading to the oxides MoO(2), U(3)O(7), V(4)O(7), and VO(2); for MoO(2)(CH(3)SO(3))(2), a small amount of MoS(2) is formed. If the thermal decomposition is carried out in a atmosphere of O(2) the oxides MoO(3) and V(2)O(5) are formed.     

Synthesis, characterization and magnetic properties of four new organically templated metal sulfates [C5H14N2][M(II)(H2O)6](SO4)2, (M(II) = Mn, Fe, Co, Ni)

A series of novel organically templated metal sulfates, [C(5)H(14)N(2)][M(II)(H(2)O)(6)](SO(4))(2) with (M(II) = Mn (1), Fe (2), Co (3) and Ni (4)), have been successfully synthesized by slow evaporation and characterized by single-crystal X-ray diffraction as well as with infrared spectroscopy, thermogravimetric analysis and magnetic measurements. All compounds were prepared using a racemic source of the 2-methylpiperazine and they crystallized in the monoclinic systems, P2(1)/n for (1, 3) and P2(1)/c for (2,4). Crystal data are as follows: [C(5)H(14)N(2)][Mn(H(2)O)(6)](SO(4))(2), a = 6.6385(10) ?, b = 11.0448(2) ?, c = 12.6418(2) ?, β = 101.903(10)°, V = 906.98(3) ?(3), Z = 2; [C(5)H(14)N(2)][Fe(H(2)O)(6)](SO(4))(2), a = 10.9273(2) ?, b = 7.8620(10) ?, c = 11.7845(3) ?, β = 116.733(10)°, V = 904.20(3) ?(3), Z = 2; [C(5)H(14)N(2)][Co(H(2)O)(6)](SO(4))(2), a = 6.5710(2) ?, b = 10.9078(3) ?, c = 12.5518(3) ?, β = 101.547(2)°, V = 881.44(4) ?(3), Z = 2; [C(5)H(14)N(2)][Ni(H(2)O)(6)](SO(4))(2), a = 10.8328(2) ?, b = 7.8443(10) ?, c = 11.6790(2) ?, β = 116.826(10)°, V = 885.63(2) ?(3), Z = 2. The three-dimensional structure networks for these compounds consist of isolated [M(II)(H(2)O)(6)](2+) and [C(5)H(14)N(2)](2+) cations and (SO(4))(2-) anions linked by hydrogen-bonds only. The use of racemic 2-methylpiperazine results in crystallographic disorder of the amines and creation of inversion centers. The magnetic measurements indicate that the Mn complex (1) is paramagnetic, while compounds 2, 3 and 4, (M(II) = Fe, Co, Ni respectively) exhibit single ion anisotropy.     

Topological evolution in uranyl dicarboxylates: synthesis and structures of one-dimensional UO2(C6H8O4)(H2O)2 and three-dimensional UO2(C6H8O4)

Two novel uranyl adipates are reported as synthesized via hydrothermal treatment of uranium oxynitrate and adipic acid. One-dimensional UO(2)(C(6)H(8)O(4))(H(2)O)(2) (1) [a = 9.6306(6) A, c = 11.8125(10) A, tetragonal, P4(3)2(1)2 (No. 96), Z = 4] consists of chains of (UO(2))O(4)(H(2)O)(2) hexagonal bipyramids tethered through a linear adipic acid backbone. Three-dimensional UO(2)(C(6)H(8)O(4)) (2) [a = 5.5835(12) A, b = 8.791(2) A, c = 9.2976(17) A, alpha = 87.769(9) degrees, beta = 78.957(8) degrees, gamma = 81.365(11) degrees, triclinic, P1 (No. 2), Z = 2] is produced by decreasing the hydration level of the reaction conditions. This structure contains a previously unreported [(UO(2))(2)O(8)] building unit cross-linked into a neutral metal-organic framework topology with vacant channels.     

Do secondary and tertiary ammonium cations act as structure-directing agents in the formation of layered uranyl selenites?

Two new layered uranyl selenites, [C(4)H(12)N(2)](0.5)[UO(2)(HSeO(3))(SeO(3))] (1) and [C(6)H(14)N(2)](0.5)[UO(2)(HSeO(3))(SeO(3))].0.5H(2)O.0.5CH(3)CO(2)H (2), have been isolated from mild hydrothermal reactions. The preparation of 1 was achieved by reacting UO(2)(C(2)H(3)O(2))(2).2H(2)O with H(2)SeO(4) in the presence of piperazine at 130 degrees C for 2 d. Crystals of 2 were synthesized by reacting UO(2)(C(2)H(3)O(2))(2).2H(2)O, H(2)SeO(4), and 1,4-diazabicyclo[2.2.2]octane at 150 degrees C for 2 d. The structure of 1 consists of UO(2)(2+) cations that are bound by bridging HSeO(3)(-) anions and chelating/bridging SeO(3)(2)(-) anions to yield UO(7) pentagonal bipyramids. The joining of the uranyl moieties by the hydrogen selenite and selenite anions creates two-dimensional 2(infinity) [UO(2)(HSeO(3))(SeO(3))](-) layers that extend in the bc-plane. The stereochemically active lone pair of electrons on the HSeO(3)(-) and SeO(3)(2)(-) anions align along the a-axis making each layer polar. The 2(infinity)[UO(2)(HSeO(3))(SeO(3))](-) layers and piperazinium cations stack in a AA'BAA'B sequence where two layers stack on one another without intervening piperazinium cations. While each 2(infinity)[UO(2)(HSeO(3))(SeO(3))](-) layer is polar, in the AA' stacking, the polarity of the second sheet is reversed with respect to the first, yielding an overall structure that is centrosymmetric. The structure of 2 is constructed from uranyl cations that are bound by three bridging SeO(3)(2)(-) and two bridging HSeO(3)(-) anions to create UO(7) pentagonal bipyramids. The linking of the uranyl cations by the HSeO(3)(-) and SeO(3)(2-) anions creates 2(infinity)[UO(2)(HSeO(3))(SeO(3))](-) layers that extend in the ac-plane. In 1 and 2, the organic ammonium cations form hydrogen bonds with the anionic uranyl selenite layers. Crystallographic data: 1, monoclinic, space group P2(1)/c, a = 10.9378(5) A, b = 8.6903(4) A, c = 9.9913(5) A, beta = 90.3040(8) degrees, Z = 4; 2, orthorhombic, space group Pnma, a = 13.0858(8) A, b = 17.555(1) A, c = 10.5984(7) A, Z = 8.     

Aqueous reactions of U(VI) at high chloride concentrations: syntheses and structures of new uranyl chloride polymers

The reactions of UO(3) with acidic aqueous chloride solutions resulted in the formation of two new polymeric U(VI) compounds. Single crystals of Cs(2)[(UO(2))(3)Cl(2)(IO(3))(OH)O(2)].2H(2)O (1) were formed under hydrothermal conditions with HIO(3) and CsCl, and Li(H(2)O)(2)[(UO(2))(2)Cl(3)(O)(H(2)O)] (2) was obtained from acidic LiCl solutions under ambient temperature and pressure. Both compounds contain pentagonal bipyramidal coordination of the uranyl dication, UO(2)(2+). The structure of 1 consists of infinite [(UO(2))(3)Cl(2)(IO(3))(mu(3)-OH)(mu(3)-O)(2)](2-) ribbons that run down the b axis that are formed from edge-sharing pentagonal bipyramidal [UO(6)Cl] and [UO(5)Cl(2)] units. The Cs(+) cations separate the chains from one another and form long ionic contacts with terminal oxygen atoms from iodate ligands, uranyl oxygen atoms, water molecules, and chloride anions. In 2, edge-sharing [UO(3)Cl(4)] and [UO(5)Cl(2)] units build up tetranuclear [(UO(2))(4)(mu-Cl)(6)(mu(3)-O)(2)(H(2)O)(2)](2-) anions that are bridged by chloride to form one-dimensional chains. These chains are connected in a complex network of hydrogen bonds and interactions of uranyl oxygen atoms with Li(+) cations. Crystal data: 1, orthorhombic, space group Pnma, a = 8.2762(4) A, b = 12.4809(6) A, c = 17.1297(8) A, Z = 4; 2, triclinic, space group P1, a = 8.110(1) A, b = 8.621(1) A, c = 8.740(1) A, Z = 2.     

Two versatile N,N'-bipyridine-type ligands for preparing organic-inorganic coordination polymers: new cobalt- and nickel-containing framework materials

The Schiff base ligands 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene (L1, monoclinic, P2(1)/c, a = 3.856(1) A, b = 11.032(2) A, c = 12.738(3) A, beta = 92.21(3) degrees, Z = 2) and 2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene (L2, monoclinic, P2(1)/c, a = 10.885(2) A, b = 4.613(1) A, c = 14.978(3) A, beta = 92.827(4) degrees, Z = 2) were used in the synthesis of four new organic-inorganic coordination polymers, each of them adopting a different structural motif. Synthesis, X-ray structural determinations, and spectroscopic and thermogravimetric analyses are presented. The reaction between Co(NO(3))(2).6H(2)O and L1 afforded a two-dimensional noninterpenetrating brick-wall structure, [Co(C(12)N(4)H(10))(1.5)(NO(3))(2)(H(2)O)(CH(2)Cl(2))(2)](n)() (1, triclinic, P1; a = 10.242(7) A, b = 10.802(7) A, c = 15.100(1) A, alpha = 70.031(1), beta = 75.168(11), gamma = 76.155(11), Z = 2), while Ni(NO(3))(2).6H(2)O combined with L1 yielded an interpenetrating three-dimensional rhombus-grid polymer, [Ni(C(12)N(4)H(10))(2)(NO(3))(2)(OC(4)H(8))(1.66)(H(2)O)(0.33)](n) (2, monoclinic, C2/c; a = 20.815(8) A, b = 23.427(8) A, c = 17.291(6) A, beta = 116.148(6), Z = 8). The reaction of Co(NO(3))(2).6H(2)O and L2 was found to be solvent-sensitive and resulted in the formation of two different noninterpenetrating compounds: [Co(C(14)N(4)H(14))(2)(NO(3))(2)(C(6)H(6))(1.5)](n)() (3, monoclinic, C2/c; a = 22.760(2) A, b = 21.010(3) A, c = 25.521(2) A, beta = 97.151(2), Z = 8), which adopts a two-dimensional square-grid motif formed by propeller-type modules, and [Co(C(14)N(4)H(14))(1.5)(NO(3))(2)(CH(2)Cl(2))(2)](n)() (4, monoclinic, P2(1)/n; a = 14.432(2) A, b = 14.543(8) A, c = 15.448(4) A, beta = 96.968(0), Z = 4), consisting of T-shaped building blocks assembled into a one-dimensional ladder-type structure. These four coordination polymers all exhibit impressive thermal stability. Thermogravimetric studies showed that after complete removal of the solvents, the frameworks are stable to temperatures between 234 degrees C and 260 degrees C.     

Excision of uranium oxide chains and ribbons in the novel one-dimensional uranyl iodates K(2)[(UO(2))3(IO(3))(4)O(2)] and Ba[(UO(2)2(IO(3))(2)O(2)](H(2)O)

The alkali metal and alkaline-earth metal uranyl iodates K(2)[(UO(2))(3)(IO(3))(4)O(2)] and Ba[(UO(2))(2)(IO(3))(2)O(2)](H(2)O) have been prepared from the hydrothermal reactions of KCl or BaCl(2) with UO(3) and I(2)O(5) at 425 and 180 degrees C, respectively. While K(2)[(UO(2))(3)(IO(3))(4)O(2)] can be synthesized under both mild and supercritical conditions, the yield increases from <5% to 73% as the temperature is raised from 180 to 425 degrees C. Ba[(UO(2))(2)(IO(3))(2)O(2)](H(2)O), however, has only been isolated from reactions performed in the mild temperature regime. Thermal measurements (DSC) indicate that K(2)[(UO(2))(3)(IO(3))(4)O(2)] is more stable than Ba[(UO(2))(2)(IO(3))(2)O(2)](H(2)O) and that both compounds decompose through thermal disproportionation at 579 and 575 degrees C, respectively. The difference in the thermal behavior of these compounds provides a basis for the divergence of their preparation temperatures. The structure of K(2)[(UO(2))(3)(IO(3))(4)O(2)] is composed of [(UO(2))(3)(IO(3))(4)O(2)](2)(-) chains built from the edge-sharing UO(7) pentagonal bipyramids and UO(6) octahedra. Ba[(UO(2))(2)(IO(3))(2)O(2)](H(2)O) consists of one-dimensional [(UO(2))(2)(IO(3))(2)O(2)](2)(-) ribbons formed from the edge sharing of distorted UO(7) pentagonal bipyramids. In both compounds the iodate groups occur in both bridging and monodentate binding modes and further serve to terminate the edges of the uranium oxide chains. The K(+) or Ba(2+) cations separate the chains or ribbons in these compounds forming bonds with terminal oxygen atoms from the iodate ligands. Crystallographic data: K(2)[(UO(2))(3)(IO(3))(4)O(2)], triclinic, space group P_1, a = 7.0372(5) A, b = 7.7727(5) A, c = 8.9851(6) A, alpha = 93.386(1) degrees, beta = 105.668(1) degrees, gamma = 91.339(1) degrees, Z = 1; Ba[(UO(2))(2)(IO(3))(2)O(2)](H(2)O), monoclinic, space group P2(1)/c, a = 8.062(4) A, b = 6.940(3) A, c = 21.67(1), beta= 98.05(1) degrees, Z = 4.     

Building unit and topological evolution in the hydrothermal DABCO-U-F system

Compounds NDUF-1 ([C(6)H(14)N(2)](UO(2))(2)F(6); P2(1)/c, a = 6.9797(15) A, b = 8.3767(15) A, c = 23.760(5) A, beta = 91.068(4) degrees, V = 1388.9(5) A(3), Z = 4), NDUF-2 ([C(6)H(14)N(2)](2)(UO(2))(2)F(5)UF(7).H(2)O), NDUF-3 ((NH(4))(7)U(6)F(31); R3, a = 15.4106(8) A, c = 10.8142(8) A, V = 2224.1(2) A(3), Z = 3), and NDUF-4 ([NH(4)]U(3)F(13)) have been synthesized hydrothermally from fixed composition reactant mixtures over variable time periods [DABCO (C(6)H(12)N(2)), UO(2)(NO(3))(2).6H(2)O, HF, and H(2)O; 2-14 days]. Observed is a systematic evolution of the structural building units within these materials from the UO(2)F(5) pentagonal bipyramid in NDUF-1 and -2 to the UF(8) trigonal prism in NDUF-2 and finally to the UF(9) polyhedron in NDUF-3 and -4 as a function of reaction time. Coupled to this coordination change is a reduction of U(VI) to U(IV) as well as a breakdown of the organic structure-directing agent from DABCO to NH(4)(+). These processes contribute to a structural transition from layered topologies (NDUF-1) to chain (NDUF-2), back to layered (NDUF-3), and ultimately to framework (NDUF-4) connectivities. The synthesis conditions, crystal structures, and possible transformation mechanisms within this system are presented.     

Mixed-metal uranium(VI) iodates: hydrothermal syntheses,structures, and reactivity of Rb[UO(2)(CrO(4))(IO(3))(H(2)O)], A(2)[UO(2)(CrO(4))(IO(3))(2)] (A = K,Rb, Cs), and K(2)[UO(2)(MoO(4))(IO(3))(2)

The reactions of the molecular transition metal iodates A[CrO(3)(IO(3))] (A = K, Rb, Cs) with UO(3) under mild hydrothermal conditions provide access to four new, one-dimensional, uranyl chromatoiodates, Rb[UO(2)(CrO(4))(IO(3))(H(2)O)] (1) and A(2)[UO(2)(CrO(4))(IO(3))(2)] (A = K (2), Rb (3), Cs (4)). Under basic conditions, MoO(3), UO(3), and KIO(4) can be reacted to form K(2)[UO(2)(MoO(4))(IO(3))(2)] (5), which is isostructural with 2 and 3. The structure of 1 consists of one-dimensional[UO(2)(CrO(4))(IO(3))(H(2)O)](-) ribbons that contain uranyl moieties bound by bridging chromate and iodate anions as well as a terminal water molecule to create [UO(7)] pentagonal bipyramidal environments around the U(VI) centers. These ribbons are separated from one another by Rb(+) cations. When the iodate content is increased in the hydrothermal reactions, the terminal water molecule is replaced by a monodentate iodate anion to yield 2-4. These ribbons can be further modified by replacing tetrahedral chromate anions with MoO(4)(2)(-) anions to yield isostructural, one-dimensional [UO(2)(MoO(4))(IO(3))(2)](2)(-) ribbons. Crystallographic data: 1, triclinic, space group P(-)1, a = 7.3133(5) A, b = 8.0561(6) A, c = 8.4870(6) A, alpha = 88.740(1) degrees, beta = 87.075(1) degrees, gamma = 71.672(1) degrees, Z = 2; 2, monoclinic, space group P2(1)/c, a = 11.1337(5) A, b = 7.2884(4) A, c = 15.5661(7) A, beta = 107.977(1) degrees, Z = 4; 3, monoclinic, space group P2(1)/c, a = 11.3463(6) A, b = 7.3263(4) A, c = 15.9332(8) A, beta = 108.173(1) degrees, Z = 4; 4, monoclinic, space group P2(1)/n, a = 7.3929(5) A, b = 8.1346(6) A, c = 22.126(2) A, beta = 90.647(1) degrees, Z = 4; 5, monoclinic, space group P2(1)/c, a = 11.3717(6) A, b = 7.2903(4) A, c = 15.7122(8) A, beta = 108.167(1) degrees, Z = 4.     

Expanding the remarkable structural diversity of uranyl tellurites: hydrothermal preparation and structures of K[UO(2)Te(2)O(5)(OH)], Tl(3)[(UO(2))(2)[Te(2)O(5)(OH)](Te(2)O(6))].2H(2)O,beta-Tl(2)[UO(2)(TeO(3))(2)], and Sr(3)[UO(2)(TeO(3))(2)](TeO(3))(2)

The reactions of UO(2)(C(2)H(3)O(2))(2).2H(2)O with K(2)TeO(3).H(2)O, Na(2)TeO(3) and TlCl, or Na(2)TeO(3) and Sr(OH)(2).8H(2)O under mild hydrothermal conditions yield K[UO(2)Te(2)O(5)(OH)] (1), Tl(3)[(UO(2))(2)[Te(2)O(5)(OH)](Te(2)O(6))].2H(2)O (2) and beta-Tl(2)[UO(2)(TeO(3))(2)] (3), or Sr(3)[UO(2)(TeO(3))(2)](TeO(3))(2) (4), respectively. The structure of 1 consists of tetragonal bipyramidal U(VI) centers that are bound by terminal oxo groups and tellurite anions. These UO(6) units span between one-dimensional chains of corner-sharing, square pyramidal TeO(4) polyhedra to create two-dimensional layers. Alternating corner-shared oxygen atoms in the tellurium oxide chains are protonated to create short/long bonding patterns. The one-dimensional chains of corner-sharing TeO(4) units found in 1 are also present in 2. However, in 2 there are two distinct chains present, one where alternating corner-shared oxygen atoms are protonated, and one where the chains are unprotonated. The uranyl moieties in 2 are bound by five oxygen atoms from the tellurite chains to create seven-coordinate pentagonal bipyramidal U(VI). The structures of 3 and 4 both contain one-dimensional [UO(2)(TeO(3))(2)](2-) chains constructed from tetragonal bipyramidal U(VI) centers that are bridged by tellurite anions. The chains differ between 3 and 4 in that all of the pyramidal tellurite anions in 3 have the same orientation, whereas the tellurite anions in 4 have opposite orientations on each side of the chain. In 4, there are also additional isolated TeO(3)(2-) anions present. Crystallographic data: 1, orthorhombic, space group Cmcm, a = 7.9993(5) A, b = 8.7416(6) A, c = 11.4413(8) A, Z = 4; 2, orthorhombic, space group Pbam, a = 10.0623(8) A, b = 23.024(2) A, c = 7.9389(6) A, Z = 4; 3, monoclinic, space group P2(1)/n, a = 5.4766(4) A, b = 8.2348(6) A, c = 20.849(3) A, beta = 92.329(1) degrees, Z = 4; 4, monoclinic, space group C2/c, a = 20.546(1) A, b = 5.6571(3) A, c = 13.0979(8) A, beta = 94.416(1) degrees, Z = 4.     

First structurally characterized actinide isocyanates

The synthesis and characterization of the neutral uranylisocyanate UO(2)(NCO)(2)(OP(NMe(2))(3))(2) [crystal data: monoclinic, P2(1)/c, a = 8.512(2) A, b = 10.931(2) A, c = 14.329(3) A, beta = 103.923(3) degrees , V = 1294.0(4) A(3), Z = 2] and isocyanato uranate (Et(4)N)(6)[(UO(2))(2)(NCO)(5)O](2) x 2CH(3)CN x H(2)O [crystal data: monoclinic, P2(1)/c, a = 17.2787(2) A, b = 15.560(1) A, c = 32.7619(4) A, beta = 94.0849(5) degrees , V = 8786.5(2) A(3), Z = 4] are reported. Not only are these compounds the first unambiguously characterized uranium isocyanates regardless of the oxidation state for uranium, but they are also the first structurally characterized actinide isocyanates. Both compounds show coordination of the OCN moiety through nitrogen to uranium and were characterized using IR and (1)H, (13)C, (14)N, and (31)P NMR spectroscopy and X-ray diffraction.     

Polyfluorinated Tris(pyrazolyl)borates. Syntheses and Spectroscopic and Structural Characterization of Group 1 and Group 11 Metal Complexes of [HB(3,5-(CF(3))(2)Pz)(3)](-) and [HB(3-(CF(3))Pz)(3)](-)

The fluorinated tris(pyrazolyl)borate ligands [HB(3,5-(CF(3))(2)Pz)(3)](-) and [HB(3-(CF(3))Pz)(3)](-) (where Pz = pyrazolyl) have been synthesized as their sodium salts from the corresponding pyrazoles and NaBH(4) in high yield. These sodium complexes and the related [HB(3,5-(CF(3))(2)Pz)(3)]K(DMAC) were used as ligand transfer agents in the preparation of the copper and silver complexes [HB(3,5-(CF(3))(2)Pz)(3)]Cu(DMAC), [HB(3,5-(CF(3))(2)Pz)(3)]CuPPh(3), [HB(3,5-(CF(3))(2)Pz)(3)]AgPPh(3), and [HB(3-(CF(3))Pz)(3)]AgPPh(3). Metal complexes of the fluorinated [HB(3,5-(CF(3))(2)Pz)(3)](-) ligand have highly electrophilic metal sites relative to their hydrocarbon analogs. This is evident from the formation of stable adducts with neutral oxygen donors such as H(2)O, dimethylacetamide, or thf. Furthermore, the metal compounds derived from fluorinated ligands show fairly long-range coupling between fluorines of the trifluoromethyl groups and the hydrogen, silver, or phosphorus. The solid state structures show that the fluorines are in close proximity to these nuclei, thus suggesting a possible through-space coupling mechanism. Crystal structures of the sodium adducts exhibit significant metal-fluorine interactions. The treatment of [HB(3,5-(CF(3))(2)Pz)(3)]Na(H(2)O) with Et(4)NBr led to [Et(4)N][HB(3,5-(CF(3))(2)Pz)(3)], which contains a well-separated [Et(4)N](+) cation and the [HB(3,5-(CF(3))(2)Pz)(3)](-) anion in the solid state. Crystal data with Mo Kalpha (lambda = 0.710 73 ?) at 193 K: [HB(3,5-(CF(3))(2)Pz)(3)]Na(H(2)O), C(15)H(6)BF(18)N(6)NaO, a = 7.992(2) ?, b = 15.049(2) ?, c = 9.934(2) ?, beta = 101.16(2) degrees, monoclinic, P2(1)/m, Z = 2; [{HB(3-(CF(3))Pz)(3)}Na(thf)](2), C(32)H(30)B(2)F(18)N(12)Na(2)O(2), a = 9.063(3) ?, b = 10.183(2) ?, c = 12.129(2) ?, alpha = 94.61(1) degrees, beta = 101.16(2) degrees, gamma = 95.66(2) degrees, triclinic, &Pmacr;1, Z = 1; [HB(3,5-(CF(3))(2)Pz)(3)]Cu(DMAC), C(19)H(13)BCuF(18)N(7)O, a = 15.124(4) ?, b = 8.833(2) ?, c = 21.637(6) ?, beta = 105.291(14) degrees, monoclinic, P2(1)/n, Z = 4; [HB(3,5-(CF(3))(2)Pz)(3)]CuPPh(3), C(33)H(19)BCuF(18)N(6)P, a = 9.1671(8) ?, b = 14.908(2) ?, c = 26.764(3) ?, beta = 94.891(1) degrees, monoclinic, P2(1)/c, Z = 4; [HB(3,5-(CF(3))(2)Pz)(3)]AgPPh(3).0.5C(6)H(14), C(36)H(26)AgBF(18)N(6)P, a = 13.929(2) ?, b = 16.498(2) ?, c = 18.752(2) ?, beta = 111.439(6) degrees, monoclinic, P2(1)/c, Z = 4; [Et(4)N][HB(3,5-(CF(3))(2)Pz)(3)], C(23)H(24)BF(18)N(7), a = 10.155(2) ?, b = 18.580(4) ?, c = 16.875(5) ?, beta = 99.01(2) degrees, monoclinic, P2(1)/n, Z = 4.     

Oxidation in nonclassical organolanthanide chemistry: synthesis, characterization, and X-ray crystal structures of cerium(III) and -(IV) amides

[Ce(NR(2))(3)] (R = SiMe(3)) with TeCl(4) in tetrahydrofuran solution gave a mixture of two major products in a combined yield of ca. 50% based on available metal: (i) the Ce(IV) amide [CeCl(NR(2))(3)] (1), which was isolated as purple needles and identified on the basis of (1)H NMR and mass spectra, microanalysis, and a single-crystal X-ray analysis [C(18)H(54)CeClN(3)Si(6), rhombohedral, R3c (No. 161), a = b = 18.4508(7) A, c = 16.8934(7) A, Z = 6]; (ii) unstable [[Ce(NR(2))(2)(mu-Cl)(thf)](2)] (2), as colorless blocks [C(32)H(88)Ce(2)Cl(2)N(4)O(2)Si(8), monoclinic, P2(1)/n (No. 14), a = 14.506(3) A, b = 13.065(3) A, c = 16.779(3) A, beta = 113.789(12) degrees, Z = 2], which readily disproportionated in solution. In toluene solution, the product 1 was obtained exclusively. The same cerium(III) amide starting material was oxidized by PBr(2)Ph(3) in diethyl ether solution to give purple [CeBr(NR(2))(3)] (3) [C(18)H(54)BrCeN(3)Si(6), rhombohedral, R3c (No. 161), a = b = 18.4113(12) A, c = 16.9631(17) A, Z = 6], along with presumed [CeBr(3)(OEt(2))(n)()], which has not been characterized but with thf, by displacement of the ether ligands, gave [CeBr(3)(thf)(4)] (4) [C(16)H(32)Br(3)CeO(4), triclinic, P1 (No. 2), a = 8.2536(7) A, b = 9.4157(5) A, c = 15.5935(14) A, alpha = 79.009(5), beta = 87.290(3) degrees, gamma = 74.835(5) degrees, Z = 2). TeBr(4) reacted with [Ce(NR(2))(3)] in thf to give small amounts of 3; the major product (although only formed in 15% yield) was monomeric [CeBr(2)(NR(2))(thf)(3)] (5) [C(18)H(42)Br(2)CeNO(3)Si(2), monoclinic, P2(1)/c (No. 14), a = 14.9421(4) A, b = 11.8134(5) A, c = 15.8317(7) A, alpha = gamma = 120 degrees, beta = 92.185(3) degrees, Z = 4].     

Amine-templated linear vanadium sulfates with different chain structures

Amine-templated vanadium sulfates of the formula [HN(CH(2))(6)NH][(V(IV)O)(2)(OH)(2)(SO(4))(2)].H(2)O, I, [H(3)N(CH(2))(2)NH(3)][V(III)(OH)(SO(4))(2)].H(2)O, II, and [H(2)N(CH(2))(4)NH(2)][(V(IV)O)(H(2)O)(SO(4))(2)], III, have been prepared under hydrothermal conditions. These vanadium sulfates add to the new emerging family of organically templated metal sulfates. Compound I has a linear chain structure consisting of V(2)O(8) square-pyramid dimers connected by corner-sharing SO(4) tetrahedra, creating four-membered rings along the chain. Both II and III possess simple linear chain topologies formed by VO(6) octahedra and SO(4) tetrahedra, with II having the tancoite chain structure. Compound I crystallizes in the triclinic space group P1 (No. 2) with a = 7.4852(4) A, b = 9.5373(5) A, c = 11.9177(6) A, alpha = 77.22 degrees, beta = 76.47(2) degrees, gamma = 80.86 degrees, Z = 2. Compound II: monoclinic, space group P2(1)/c (No. 14), a = 6.942(2) A, b = 10.317(3) A, c = 15.102(6) A, beta = 90.64(4) degrees, Z = 4. Compound III: triclinic, space group P1 (No. 2) with a = 6.2558(10) A, b = 7.0663(14) A, c = 15.592(4) A, alpha = 90.46(2) degrees, beta = 90.47(2) degrees, gamma = 115.68(2) degrees, Z = 2. Magnetic susceptibility measurements reveal weak antiferromagnetic interactions in I and III and ferromagnetic interactions in II.     

Hydrothermal Synthesis, Crystal Structure and Luminescent Properties of an Organically Templated 2-D Uranyl Sulfate

An organically templated 2-D uranyl sulfate, {（C2H8N）[（UO2）Cl（SO4）（H2O）] }n 1, has been hydrothermally synthesized. The crystal and molecular structures have been determined by X-ray crystallography method and spectral techniques. 1 belongs to monoclinic, space group P21/c with a = 8.3545（17）, b = 10.550（2）, c = 12.370（3）A, β = 102.64（3）°, V = 1063.9（4）A3, Mr = 464.64, De= 2.901 g/cm^3, F（000） = 836,μ = 15.710 mm^-1, Z= 4, the final R = 0.0286 and wR = 0.0685 for 10164 observed reflections with Ⅰ 〉 2σ（Ⅰ）. 1 presents a two-dimensional layer-like structure constructed from infinite anionic [（UO2）Cl（H2O）（SO4）]^- layers with [C2H8N]^＋ cations balancing the charge and a number of intermoleeular hydrogen bonds （C-H…O and O-H…Cl） existing in the solid state. The fluorescence properties of 1 have also been discussed.     

Structural and spectroscopic trends in actinyl iodates of uranium,neptunium, and plutonium

Two neptunyl(VI) iodates, NpO(2)(IO(3))(2)(H(2)O) (1) and NpO(2)(IO(3))(2).H(2)O (2), have been prepared from the aqueous reactions of Np(V) in HCl with KIO(4) or H(5)IO(6) at 180 degrees C and have been characterized by single crystal X-ray diffraction and Raman spectroscopy. Both compounds consist of two-dimensional arrangements of pentagonal bipyramidal [NpO(7)] polyhedra with axial neptunyl, NpO(2)(2+), dioxocations. In 1, the neptunium centers are bound in the equatorial plane by four bridging iodate anions and one terminal water molecule. The iodate anions link the [NpO(7)] units into corrugated sheets that interact with one another through intermolecular IO(3)(-)...IO(3)(-) interactions as also observed in UO(2)(IO(3))(2)(H(2)O). Compound 2 is isostructural with the recently reported PuO(2)(IO(3))(2).H(2)O, where oxygen atoms from bridging iodate anions occupy the five equatorial sites around the neptunyl moieties. The iodate anions occur as both mu(2)- and mu(3)-units and link the neptunyl polyhedra into sheets. Both types of iodate anions have their stereochemically active lone-pair of electrons aligned on one side of each layer creating a polar structure. Raman spectra of 1, UO(2)(IO(3))(2)(H(2)O), and PuO(2)(IO(3))(2).H(2)O show a sequential shift of the nu(1)(AnO(2)(2+)) stretch to lower wavenumber as the atomic number of the actinide is increased. Crystallographic data: 1, orthorhombic, space group Pcan, a = 7.684(2) A, b = 8.450(2) A, c = 12.493(3) A, Z = 4; 2, orthorhombic, space group Pna2(1), a = 7.314(1) A, b = 11.631(2) A, c = 9.449(2) A, Z = 4.     

The role of amine sulfates in hydrothermal uranium chemistry

A series of novel uranium sulfates containing organic structure directing cations has been synthesized from amine sulfate precursors under hydrothermal conditions. The amine sulfates act as a soluble source of the protonated amines and sulfate ions at low temperature and provide a reaction pathway in which no amine decomposition is observed. The protonated amines act as both space fillers and hydrogen-bond donors in the three-dimensional structure. The factors governing the formation of the observed hydrogen-bonding networks were probed through the use of bond valence sums, which allow the quantification of residual negative charge and determination of the relative nucleophilicity of each oxide ligand. The hydrogen bonding in these new compounds is dependent upon two factors. First, the oxide ligands with the highest nucleophilicities are preferential acceptors with respect to their less nucleophilic counterparts. Second, geometric constraints that result from the formation of multiple hydrogen bonds from a single ammonium center can dictate the donation to oxides with smaller negative charges. Crystal data for [N4C6H12][SO4]2 x 2H2O, a = 7.2651(2) A, b = 7.3012(2) A, c = 8.3877(3) A, alpha = 90.260(1) degrees, beta = 100.323(1) degrees, gamma = 113.0294(15) degrees, triclinic, P-1 (No. 2), Z = 1; for [N4C6H22][UO2(H2O)(SO4)2]2 x 6H2O, a = 6.7318(1) A, b = 9.2975(1) A, c = 13.1457(3) A, alpha = 72.3395(6) degrees, beta = 89.1401(7) degrees, gamma = 70.0267(12) degrees, triclinic, P-1 (No. 2), Z = 1; for [N4C6H22][UO2(SO4)2)2, a = 9.3771(2) A, b = 12.9523(3) A, c = 18.9065(6) A, orthorhombic, Pbca (No. 61), Z = 4; for [N5C8H28]2[(UO2)5(H2O)5(SO4)10] x H2O, a = 7.76380(5) A, b = 14.16890(5) A, c = 56.46930(5) A, orthorhombic, Pbnm (No. 62), Z = 4.     

Hydrothermal preparation of nickel(II)/uranium(IV) fluorides with one-, two-, and three-dimensional topologies

A modified compositional diagram for the reactions of Ni(C(2)H(3)O(2))(2).4H(2)O with UO(2)(C(2)H(3)O(2))(2).2H(2)O and HF in aqueous media under mild hydrothermal conditions (200 degrees C) has been completed to yield three Ni(II)/U(IV) fluorides, Ni(H(2)O)(4)UF(6).1.5H(2)O (1), Ni(2)(H(2)O)(6)U(3)F(16).3H(2)O (2), and Ni(H(2)O)(2)UF(6)(H(2)O) (3). The structure of 1 consists of one-dimensional columns constructed from two parallel chains of edge-sharing dodecahedral [UF(8)] units. The sides of the columns are terminated by octahedral Ni(II) units that occur as cis-[Ni(H(2)O)(4)F(2)] polyhedra. In contrast, the crystal structure of 2 reveals a two-dimensional Ni(II)/U(IV) architecture built from edge-sharing tricapped trigonal prismatic [UF(9)] units. The top and bottom of the sheets are capped by fac-[Ni(H(2)O)(3)F(3)] octahedra. The structure of 3 is formed from [UF(8)(H(2)O)] tricapped trigonal prisms that edge share with one another to form one-dimensional chains. These chains are then joined together into a three-dimensional network by corner sharing with trans-[Ni(H(2)O)(2)F(4)] octahedra. Crystallographic data: 1, orthorhombic, space group Cmcm, a = 14.3383(8) A, b = 15.6867(8) A, c = 8.0282(4) A, Z = 8; 2, hexagonal, space group P6(3)/mmc, a = 7.9863(5) A, c = 16.566(1) A, Z = 2; 3, monoclinic, space group C2/c, a = 12.059(1) A, b = 6.8895(6) A, c = 7.9351(7) A, beta = 92.833(2) degrees, Z = 4.