3d Diphosphonates - American Chemical Society

Oct 12, 2014 - Use of 2,2-Bipyrimidine for the Preparation of UO2. 2+-3d. Diphosphonates. Pius O. Adelani,. †. Nathaniel D. Cook,. † and Peter C. ...
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Use of 2,2-Bipyrimidine for the Preparation of UO22+-3d Diphosphonates Pius O Adelani, Nathaniel D. Cook, and Peter C Burns Cryst. Growth Des., Just Accepted Manuscript • DOI: 10.1021/cg500972w • Publication Date (Web): 12 Oct 2014 Downloaded from http://pubs.acs.org on October 19, 2014

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Use of 2,2-Bipyrimidine for the Preparation of UO22+-3d Diphosphonates

Pius O. Adelani1, Nathaniel D. Cook1, and Peter C. Burns*1,2 1

Department of Civil and Environmental Engineering and Earth Sciences and 2Department of Chemistry P

and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556

A Submission to Crystal Growth & Design *[email protected] RECEIVED DATE

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ABSTRACT Three new multidimensional bimetallic UO22+-3d three dimensional complexes were crystallized in high yield under mild hydrothermal conditions: [Mn(H2O)]2[(UO2)4(PO3C6H4PO3)3(bipym)]·2H2O (1),

[Ni(H2O)]2[(UO2)3(O3PC6H4PO3)(O3PC6H4PO3H)2(bipym)]·6H2O

(2),

and

Zn[(UO2)(HO3PC6H4PO3)(HO3PC6H4PO3H)0.5(bipym)0.5] (3), where bipym = 2,2-bipyrimidine. The structure of 1 is composed of edge-sharing dimers of uranyl pentagonal bipyramids that are linked by rigid phenyl spacers to form pillared three-dimensional networks. This compound is remarkable in that the [Mn2(H2O)2(bipym)]4+ moiety is incorporated within the uranyl phosphonate frameworks without reducing the dimensionality of the overall structure. Compound 2 consists of uranyl tetragonal and pentagonal bipyramids that are linked by phosphonate groups to form a pillared three-dimensional framework with channels that are occupied by the [Ni2(H2O)2(bipym)2]4+ moiety. In compound 3, edgesharing dimers of uranyl pentagonal bipyramids are connected through the phosphonate ligand to create corrugated uranyl-phosphonate chains. The incorporated [Zn2(bipym)]4+ subunits are located within the interlayer of the uranyl-phosphonate chains. All three compounds are characterized by absorption, fluorescence, and infrared spectroscopy.

INTRODUCTION ACS Paragon Plus Environment

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Interest in the design of heterometallic uranyl-organic coordination polymers has resulted in a series of compounds with a broad range of structural diversities that have been studied for their potential in various chemical applications such as photochemistry,1-3 gas sorption,1f-g ion-exchange,4 intercalation chemistry,5 ionic conductivity,6 non-linear optics,7 magnetic interactions,8 etc. Investigating the nature and structure of compounds formed between actinide metals and other elements such as lanthanides and d-block elements is important for expanding our understanding of the electronic effects and physicochemical properties of actinides, and in turn driving its development. The two most successful synthetic strategies employed for designing bimetallic UO22+/Ln3+ or d-block metal phosphonates are (1) the logical design of bifunctional ligands with differential coordination affinity for uranyl cations and lanthanides or d-block elements, and (2) the use of an appropriate N-donor secondary linker along with phosphonates to stabilize the softer metal center. 1,3 The coordination chemistry of uranium is mostly dominated by U(VI), and linkages of uranyl polyhedra commonly yields low-dimensional layered structures containing tetragonal, pentagonal, and hexagonal bipyramidal geometries.9 The phase transitions of the uranyl phenylphosphonates is perhaps amongst the most intriguing, yielding the first uranyl nanotubule upon exposure of the uranyl phenylphosphonates to Na+/Ca2+ cations in aqueous solution.10 Interestingly, we have also shown that the reaction of the rigid benzenediphosphonate ligand and uranyl salt in the presence of Cs+/Rb+ cations resulted in uranyl diphosphonate nanotubules with an elliptical cross-section.4a-b This nanotubular compound exhibits exceptional ion-exchange properties towards monovalent cations. Several studies involving bimetallic uranyl-organic coordination polymers have showcased the importance of secondary N-donor linkers in stabilizing the non-uranyl metal centers.3 Unfortunately, the surface of the bimetallic coordination polymers are passivated by the phenyl rings, thus truncating the dimensionality of the structures.3 We recently employed bipym as secondary linkers to incorporate Cu(II) ions into nanotubular uranyl diphosphonates without truncating the structure topology.11 As an expansion of this work, we have incorporated Mn2+, Ni2+, and Zn2+ ions into this system. Herein, we ACS Paragon Plus Environment

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report the synthesis, crystal structures, and spectroscopic properties of three new multidimensional UO22+- 3d diphosphonate complexes.

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EXPERIMENTAL Synthesis. UO2(NO3)2·6H2O (98%, International Bio-Analytical Industries), MnCl2·4H2O (≥ 98%,

Aldrich),

Ni(NO3)2·6H2O

(99%,

Acros

Organics),

ZnCl2

(≥

97%,

Aldrich),

1,4-

benzenebisphosphonic acid (98%, Epsilon Chimie), 2,2′-bipyrimidine (95%, Aldrich), and HF (48 wt %, Aldrich) were used as received. All the experiments were conducted using distilled and Millipore filtered water with a resistance of 18.2 MΩ·cm. Caution! Although isotopically depleted uranium was used in these experiments, it is essential to ensure that all necessary precautions for handling radionuclides are followed, and all studies reported herein were performed in a laboratory dedicated to studies of radioactive materials. [Mn(H2O)]2[(UO2)4(PO3C6H4PO3)3(bipym)]·2H2O

(1),

[Ni(H2O)]2[(UO2)3(O3PC6H4PO3)(O3PC6H4PO3H)2(bipym)]·6H2O

and

(2),

Zn[(UO2)(HO3PC6H4PO3)(HO3PC6H4PO3H)0.5(bipym)0.5] (3). 1: UO2(NO3)2·6H2O (50.2 mg, 0.1 mmol), MnCl2·4H2O (19.5 mg, 0.1 mmol), 1,4-benzenebisphosphonic acid (23.8 mg, 0.1 mmol), 2,2bipyrimidine (15.8 mg, 0.1 mmol), 1.0 mL of water, and HF (~15µL). Reagents were sealed in PTFElined Parr 4749 autoclaves with a 23 mL internal volume. Vessels were heated statically at 160 o C in a P

P

box furnace for 5 days, and then were cooled to 25 ºC at an average rate of 9 o C/hr. The mother liquor in P

each case was decanted from the resulting products that were washed with distilled water and methanol, and allowed to dry in air. Compounds 2 and 3 were synthesized as above using Ni(NO3)2·6H2O (29.1 mg, 0.1 mmol) and ZnCl2 (13.6 mg, 0.1 mmol) for the transition metal salts, respectively. Yellow, yellow-green, and yellow blocky crystals of 1, 2, and 3 were isolated from the reaction products, respectively. The yields for compounds 1, 2, and 3 are 73%, 77%, and 69%, respectively, on the basis of uranium. Crystallographic Studies. Single crystals of compounds 1-3 were isolated from the bulk products and mounted on a cryoloop. Reflections were collected using 0.5° ω scans on a Bruker APEXII Quazar CCD X-ray diffractometer using a IµS X-ray source and a 30 W microfocused sealed tube (Mo ACS Paragon Plus Environment

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Kα, λ = 0.71073 Å) with a monocapillary collimator. The APEXII software was used for data integration and absorption corrections. The program suite SHELXTL was used for space group determination (XPREP). Structures were solved by direct methods (XS) and refined using least-squares techniques (XL).12a All atoms except hydrogen were located in the difference-Fourier maps and their positions were refined. The hydrogen atoms around the phenyl rings were added using riding models. All of the atoms were refined anisotropically in the final refinement cycles, except hydrogen. Figures were prepared using CrystalMaker for Windows.12b Selected crystallographic details are given in Table 1 and the Supporting Information, Tables S1–S3. Powder X-ray Diffraction (XRD). Powder X-ray diffraction patterns for compounds 1-3 were collected using a Bruker D8 Advance Davinci Diffractometer equipped with a Lynxeye one-dimensional solid-state detector and Cu Kα radiation at room temperature. The data collections were performed over the angular range of 5° to 55° (2θ) with a step width of 0.02° and a fixed counting time of 15 s/step. The data were used to verify the purity of the compounds and that the single crystals were representative of the bulk products (see Supporting Information, Figures S1-3). Absorption and fluorescence Spectroscopy. Room temperature solid-state absorption and fluorescence data were acquired using a Craic Technologies UV-vis-NIR microspectrophotometer with a fluorescence attachment. The absorption data were collected in the range of 250–1200 nm (Supporting Information, Figure S4). Resulting fluorescence spectra were collected between 450 and 650 nm with excitation achieved using 365 nm light from a mercury lamp (Supporting Information, Figure S5). Infrared Spectroscopy. Infrared spectra for compounds 1-3 were collected using a SensIR Technology IlluminatIR FT-IR microspectrometer (Supporting Information, Figure S6). Single crystals of compounds 1-3 were placed on a glass slide and the spectra were collected from 650 to 4000 cm-1 using a diamond ATR objective. Thermogravimetric/Differential

Scanning

Analysis.

TGA/DSC

measurements

were

conducted for 1 and 2 using a Mettler Toledo High Temperature TGA/DSC-1 for ~ 5 mg of each sample

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in an alumina crucible under dry nitrogen gas (50 mL/min). Each sample was heated from 25 to 900 °C at a rate of 20 °C/min (see Supporting Information, Figures S7 & S8).

Results Structure of [Mn(H2O)]2[(UO2)4(PO3C6H4PO3)3(bipym)]·2H2O (1). The structure of 1 is composed of edge-sharing dimers of uranyl cations that occur in pentagonal bipyramidal geometries. These uranyl cations are linked by the rigid phenyl spacers to form pillared three-dimensional networks as shown in Figure 1. In addition, this compound is remarkable in that it incorporates the [Mn2(H2O)2(bipym)]4+ subunit within the uranyl phosphonate framework without reducing the dimensionality of the overall structure.3 The Mn(II) ions are stabilized by the bipym moiety and exhibit an octahedral MnN2O4 geometry (see Figure 2). The uranyl cations in 1 are coordinated to two oxygen atoms in a nearly linear arrangement with average U═O bond distances for U(1) and U(2) at 1.776(3) Å and 1.775(3) Å, respectively. Five oxygen atoms from the diphosphonate groups coordinate the uranyl cations in the equatorial plane, with U—O bond distances ranging from 2.246(3) to 2.622(3) Å. The calculated bond-valence sums (BVSs) for U(1) and U(2) are 6.01 and 6.03 valence units, respectively.13 The phosphonate groups help to stabilize the Mn(II) cations in addition to ligating the uranyl cations. Three crystallographically distinct phosphonate groups are present in 1 and the P—O bond lengths range from 1.489(3) to 1.562(3) Å. A six-coordinate Mn(1) center is present and is coordinated by three oxygen atoms from PO3 moieties, one chelating bipym, and a coordinated water molecule. The thermogravimetric analysis revealed a weight loss of 4.3 % between approximately 150 and 300 °C that is attributed to the removal of bound water molecules (see Supporting Information, Figure S7). The Mn—Owater bond distance of 2.252(3) Å is longer than the Mn—Ophosphonate bond distances that range from 2.072(3) to 2.244(3) Å. The Mn—N bond distances are 2.303(4) and 2.356(4) Å; they are within the range of values reported in the literature.1e The calculated BVS for the Mn(1) cation is 1.83 valence units, consistent with the Mn(II) oxidation state.13

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Structure of [Ni(H2O)]2[(UO2)3(O3PC6H4PO3)(O3PC6H4PO3H)2(bipym)]·6H2O (2). The structure of compound 2 is built from two crystallographically unique uranyl cations that occur as UO6 tetragonal and UO7 pentagonal bipyramids. A view along [100] shows the edge-sharing sevencoordinate uranyl cations that are linked to the monomeric six-coordinate uranyl cations by phosphonate groups to form a pillared three-dimensional framework with channels that are filled with the [Ni2(H2O)2(bipym)3]4+ subunit (Figure 3). In contrast to compound 1, the six-coordinate Ni(II) cation is bound to two bipyms and a water molecule; this subunit is anchored within the channel by an oxygen atom of the PO3 moiety (see Figure 4). The average uranyl U═O bond lengths for U(1) and U(2) are 1.771(7) Å, while the equatorial U−O bonds range from 2.321(7) to 2.523(6) Å for U(1), and 2.255(7) to 2.304(6) Å for U(2). The calculated BVSs for the uranium cations are 6.06 and 6.01 valence units, consistent with the formal valence of U(VI).13 Three crystallographically distinct PO3 moieties are present in the structure and the P—O bond distances range from 1.494(7) to 1.596(5) Å. An oxygen atom from the PO3 moiety and a water molecule are coordinated to the octahedrally coordinated Ni(1) center with Ni—O bond lengths of 2.005(7) and 2.043(7) Å, respectively. The thermogravimetric analysis reveals ~6.3 % weight loss between 150 °C and 300 °C that is consistent with removal of the water molecules from the structure (see Supporting Information, Figure S8). The remaining four octahedral sites are occupied by N-atoms from two bipyms as shown in Figure 4. The Ni—N bonds are longer than the Ni—O bonds, and range from 2.074(9) to 2.113(9) Å, within the range of values in the literatures.1b The calculated BVS for Ni(1) is 1.96 valence units, in agreement with the assigned oxidation state of Ni(II).13 Structure of Zn[(UO2)(HO3PC6H4PO3)(HO3PC6H4PO3H)0.5(bipym)0.5] (3). The structure of 3 is built from a uranyl cation in an overall pentagonal bipyramidal geometry. This uranyl cation dimerises through shared polyhedral edges. The dimers are subsequently connected through the phosphonate ligand to form corrugated uranyl-phosphonate chains, as shown in Figure 5. The incorporated [Zn2(bipym)]4+ subunits are linked by the diphosphonate ligands into nearly linear chains that are positioned between the uranyl-phosphonate layers. The local coordination environment around the Zn(1) ACS Paragon Plus Environment

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cation contains five ligands in a distorted a trigonal bipyramidal ZnN2O3 arrangement (see Figure 6). The equatorial plane of the bipyramid is defined by two O and one N atom, with the Zn2+ cation located 0.26 Å above the plane. The angle between the apical ligands and the Zn2+ cation, O11-Zn1-N2, is 163.6°. The preference of Zn(1) for a five-coordinate geometry with respect to six-coordinate geometry as noted in 1-2 may be due to the size of the cations. The uranyl cation is bound to two “yl” oxygen atoms with an average U═O bond distance of 1.771(4) Å. In addition, five oxygen atoms from the phosphonate groups are coordinated to the uranyl center in the equatorial plane with U—O bond distances that range from 2.310(5) to 2.554(4) Å. Using these bond lengths, the calculated BVS for U(1) is 5.96 valence units, which agrees with the assigned oxidation state of U(VI).13 The two similar P(2)−O(6) and P(3)−O(10) bond distances of 1.596(5) Å reveal the presence of a P−OH group; they correspond to terminal phosphonate groups and are longer than the P—O bonds that range from 1.500(5) to 1.556(4) Å. Three sites of the five-coordinate Zn(1) center are occupied by oxygen atoms from phosphonate groups and the remaining two sites are nitrogen atoms of bipym. The Zn—N bond distances of 2.127(6) and 2.042(7) Å are longer than the Zn—O bonds that range from 1.943(4) to 2.022(4) Å. The bond valence sum for Zn(1) is 1.95 valence units, which agrees with the Zn(II) oxidation state.13 Spectroscopic Properties. The absorption spectra for compounds 1-3 are provided in Figure S4 of the Supporting Information. The assignments of peaks and descriptions were given in our earlier work.1b,c,14 The absorption spectra consist of the characteristic equatorial U–O and axial U=O charge transfer bands (approximately 325 and 425 nm) that are usually observed for uranyl-bearing complexes. Additional absorbance peaks were also observed near the infrared region (∼760 nm) for 1 and around the visible region (∼590 nm) for 2. These peaks correspond to the d-d transition of the Mn2+ and Ni2+ metal ions. It is interesting to note that the observed d-d transitions in 1 and 2 are due to the 3d5 and 3d8 configurations of the Mn2+ and Ni2+ metal ions, respectively. For compound 3, the Zn2+ metal ion with 3d10 configuration has no d-d transition, therefore no absorption feature was observed for the incorporated Zn2+ metal ion. It has been shown that incorporation of Cu2+ metal ions into uranyl 9 ACS Paragon Plus Environment

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complexes can diminish the emission from the uranyl cations.15 This is commonly observed where the aromatic system can promote the overlap of emission from uranyl cations and the d–d absorption band of copper(II) ions, yielding energy transfer and nonradiative decay.15 The fluorescence spectra of the three compounds show four well-resolved peaks at 486, 543, 586, and 611 nm and some shoulders. Compounds 1-3 are red-shifted with respect to the benchmark, the uranyl nitrate hexahydrate spectrum (487, 509, 532, 558, 586, and 612 nm). As one would expect, these results demonstrate that the energy transfer to the d-block elements may be qualitatively less efficient in encouraging quenching of the emission from uranyl cations. The IR spectra confirm the characteristic bands for asymmetric and symmetric stretching modes of the uranyl cation, ranging from 821-974 cm-1 for 1, 824-986 cm-1 for 2, and 819-965 cm-1 for 3. The series of peaks present in the spectra from 1024-1146 cm-1 in 1, 1030-1144 cm-1 in 2, and 1028-1144 cm-1 in 3, are characteristic of the P−O symmetric and asymmetric stretching modes of phosphonates. The intense and sharp peaks around 1420 cm-1 are assigned to the C—H bending in the phenyl ring, whereas the characteristic stretching modes of the bipym rings are associated with the other peaks around 1580 cm-1.16 The broad series of peaks around high-energy regions ~3500 cm-1 are characteristic of the O−H stretches of the lattice water and Mn2+/Ni2+-coordinated water in 1 and 2.1b,c,3b,14a,b,e

Discussion The addition of HF to the reactions is essential for the formation of suitable crystals for X-ray analysis. Its absence in the reactions resulted in the isolation of powder products. Surprisingly, the powder XRD patterns collected from the bulk products (without HF) are unmatchable with the simulated single crystals pattern. This suggests additional roles for the HF in the reactions, other than as mineralizing agents, and we hope to examine this in greater details in our future studies. The incorporation of a variety of transition metal ions in this system offers more flexible coordination geometries relative to Cu2+ ions.11 Although similar synthetic conditions were used, different structure topologies were obtained for Mn(II), Ni(II), and Zn(II) incorporated uranyl diphosphonate complexes. ACS Paragon Plus Environment

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This can be attributed to the disparity in sizes of the transition metal ions, their electronic configurations, the presence of different counter ions (i.e. nitrate versus chloride) and the preference for certain coordination modes. For instance, the Zn2+ ion (d10 configuration) has no ligand field constraints on its coordination geometry. The use of bipym in this study presents the additional benefit of improving the structural networks. Most of the earlier studies on the use of mono/bidentate N-donor secondary linkers yielded either 1D or 2D networks.3 The use of bipym has yielded a series of three-dimensional uranylcopper(II) diphosphonate complexes.11 Our previous experience with uranyl-copper(II) diphosphonates suggests that the secondary linker can also promote separate bimetallic phases. Interestingly, preparation of each of these complexes was carried out in one-pot reactions under hydrothermal conditions in a sealed vessel without the formation of separate monometallic or bimetallic phases. Compound 1 represents the first report of a Mn2+/UO22+ bimetallic complex to be constructed with bipym. In this structure, the uranyl dimers share common features with the nanotubular Cu2+/UO22+ diphosphonates, except that the dimers are arranged in perpendicular patterns.11 Of the few examples of Mn2+/UO22+ bimetallic complexes constructed from carboxyphosphonate groups, the most obvious similarity is found in the octahedral geometry of the manganese(II) cation.1e,g The uranyl-phosphonate chains in 2 are composed of UO7 dimers and UO6 coordination environments similar to what we reported in [H3O]2[Cu(H2O)]2[(UO2)3(PO3C6H4CO2)4]·3H2O and Cu{(UO2)(C6H4PO3)2(bipym)}·H2O complexes.1c,11 The structure of 2 is distinct from the other two compounds in that the nickel atom is bound to two bipym groups, resulting in the [Ni2(H2O)2(bipym)3]4+ subunit. This structural feature is consistent with an octahedral environment reported in [UO2Ni(SB)2(bipym)(H2O)2]·3H2O (where SB = 2-sulfobenzoate).17a A similar observation was reported in a uranyl-copper(II) heterometallic complex where a copper atom is chelated by two bipym molecules.17b The octahedrally coordinated Mn(II) and Ni(II) metal centers in 1 and 2, respectively, are distorted orthorhombically, along the C2 axis. Earlier studies on bimetallic Zn2+/UO22+ complexes using N-donor secondary linkers along with phosphonates/phosphates demonstrate the rich coordination chemistry of zinc that includes 4, 5, and 6coordination geometries.3 The incorporation of [Zn2(bipym)]4+ subunits in compound 3 is ACS Paragon Plus Environment

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unprecedented. Of the know polymetallic zinc(II)-uranyl phosphonate/phosphate complexes, the trigonal bipyramids are well documented.3

Conclusions In this report, we have expanded on a new strategy for building three dimensional bimetallic UO22+─3d complexes by using bipym as secondary linkers. Incorporation of a series of transition metals into the uranyl diphosphonate systems illustrates the richness of this synthetic strategy in designing multidimensional bimetallic complexes with a variety of structure topologies and coordination modes. Interestingly, these compounds are isolated as single-phase crystals unlike our first reported work on Cu2+ ions.11 One possible explanation is that the transition metal ions used in this work have more flexible geometries than Cu2+ ions. Multidimensional bimetallic actinide─3d materials hold great promise for the development of new compounds with unique topologies, physico-chemical, and electronic properties for magnetic and other applications. Moreover, we believe this approach represents a new strategy to create electron rich actinide materials where U(VI) (5f0) can be replaced with U(IV), Np(VI), and other transuranium elements.

Acknowledgments We thank the Center for Sustainable Energy at Notre Dame (cSEND) Materials Characterization Facilities for the use of the Bruker D8 Advance Davinci Powder X-Ray Diffractometer and Bruker Apex II Single Crystal X-Ray Diffractometer. This material is supported by the Chemical Sciences, Geosciences and Biosciences Division, Office of Basic Energy Sciences, Office of Science, U.S. Department of Energy, Grant No. DE-FG02-07ER15880.

SUPPORTING INFORMATION AVAILABLE: Selected interatomic distances and angles (Tables S1-3), powder X-ray diffraction patterns (Fig. S1-3), absorption and fluorescence spectra (Figs. S4-5), infrared spectra (Fig. S6), TGA/DSC (Figs. S7-8), and crystallographic data (CIF) of the three

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multidimensional UO22+─3d diphosphonate complexes. This material is available free of charge via the Internet at http://pubs.acs.org.

Figure Captions

Figure 1. A view along [100] showing the arrangement of the three-dimensional uranyl diphosphonate network and the incorporated Mn(II) cations including bipym in 1. Legend: UO6 units = yellow, manganese = dark blue, phosphorus = magenta, oxygen = red, nitrogen = blue, carbon = black. Hydrogen atoms are omitted for clarity.

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Figure 2. Depiction of the local coordination environments in 1 reveals the octahedrally coordinated Mn(II) cations and the bipym. The phenyl rings of the phosphonates are truncated for clarity. Ellipsoids are shown at the 50% probability level.

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Figure 3. An illustration projected down [100] showing the packing of the three-dimensional uranyl diphosphonate units and the incorporated nickel(II) cations including bipym in 2. Legend as in Figure 1, except nickel = green.

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Figure 4. Representation of the local coordination environments around the octahedrally coordinated nickel(II) cations in 2 and the bipym. The phenyl rings of the phosphonates are truncated for clarity. Ellipsoids

are

shown

in

the

50%

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Figure 5. A view down [100] showing the uranyl diphosphonate chains in 3 and the incorporated zinc(II) cations between the layers including bipym linkers. Legend as in Figure 1, except zinc = orange.

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Figure 6. Depiction of the local coordination environments around the trigonal bipyramidal zinc(II) metal center in 3 and the bipym. The phenyl rings of the phosphonates are truncated for clarity. Ellipsoids are shown at the 50% probability level.

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Table

Crystal Growth & Design

1.

Crystallographic

Data

for

[Mn(H2O)]2[(UO2)4(PO3C6H4PO3)3(bipym)]·2H2O

[Ni(H2O)]2[(UO2)3(O3PC6H4PO3)(O3PC6H4PO3H)2(bipym)]·6H2O

(2),

(1), and

Zn[(UO2)(HO3PC6H4PO3)(HO3PC6H4PO3H)0.5(bipym)0.5] (3). Compound

1

2

3

Formula Mass

1057.13

2073.94

765.53

Color and Habit

yellow, tablet

yellow-green, tablet

yellow, tablet

Space Group

P21/m (No. 11)

P 1 (No. 2)

P 1 (No. 2)

a (Å)

9.6487(15)

9.961(3)

9.647(3)

b (Å)

16.249(3)

11.128(3)

10.238(3)

c (Å)

14.644(2)

14.199(4)

12.115(4)

α (˚)

90

107.204(4)

74.141(15)

β (˚)

101.272(2)

90.137(4)

77.673(15)

γ (˚)

90

115.826(4)

69.499(14)

V (Å)

2251.7(6)

1337.4(7)

1069.0(6)

Z

4

1

2

T (K)

100

100

100

λ (Å)

0.71073

0.71073

0.71073

ρcalcd (g cm-3)

3.118

2.575

2.378

µ (Mo Kα) (mm-1)

15.195

10.027

8.970

R(F) for Fo2 > 2σ (Fo 2 )a

0.023

0.050

0.038

Rw(Fo2)b

0.060

0.105

0.084

a

R ( F ) = Σ || F0 | − | Fc || / Σ | F0 | . b R ( F02 ) = [Σw( F02 − Fc2 ) 2 / Σw( F04 )]1/ 2

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References 1. a) Knope, K. E.; de Lill, D. T.; Rowland, C. E.; Cantos, P. M.; de Bettencourt-Dias, A.; Cahill, C. L. Inorg. Chem. 2012, 51, 201. b) Adelani, P. O.; Oliver, A. G.; Albrecht-Schmitt, T. Inorg. Chem. 2012, 51, 4885. c) Adelani, P. O.; Albrecht-Schmitt, T. Crystal Growth & Design 2011, 11, 4676. d) Adelani, P. O.; Oliver, A. G.; Albrecht-Schmitt, T. E. Crystal Growth & Design

2011, 11, 3072. e) Alsobrook, A. N.; Alekseev, E. V.; Depmeier, W.; Albrecht-Schmitt, T. Crystal Growth & Design 2011, 11, 2358. f) Alsobrook, A. N.; Hauser, B. G.; Hupp, J. T.; Alekseev, E. V.; Depmeier, W.; Albrecht-Schmitt, T. Crystal Growth & Design 2011, 11, 1385. g) Alsobrook, A. N.; Hauser, B. G.; Hupp, J. T.; Alekseev, E. V.; Depmeier, W.; AlbrechtSchmitt, T. E. Chem. Commun. (Cambridge, U. K.) 2010, 46, 9167. h) Knope, K. E.; Cahill, C. L. Eur. J. Inorg. Chem. 2010, 1177. i) Alsobrook, A. N.; Zhan, W.; Albrecht-Schmitt, T. E. Inorg. Chem. (Washington, DC, U. S.) 2008, 47, 5177. j) Loiseau, T.; Mihalcea, I.; Henry, N.; Volkringer, C. Coord. Chem. Rev. 2014, 266, 69-109. 2. a) Nelson, A. D.; Rak, Z.; Albrecht-Schmitt, T.; Becker, U.; Ewing, R. C. Inorg. Chem. 2014, 53, 2787. b) Tian, T.; Yang, W.; Wang, H.; Dang, S.; Sun, Z. Inorg. Chem. 2013, 52, 8288. c) Nelson, A. D.; Albrecht-Schmitt, T. E. C. R. Chim. 2010, 13, 755. d) Nelson, A. D.; Bray, T. H.; Stanley, F. A.; Albrecht-Schmitt, T. E. Inorg. Chem. (Washington, DC, U. S.) 2009, 48, 4530. e) Nelson, A. D.; Bray, T. H.; Albrecht-Schmitt, T. E. Angew. Chem., Int. Ed. 2008, 47, 6252. f) Diwu, J.; Wang, S.; Good, J. J.; DiStefano, V. H.; Albrecht-Schmitt, T. Inorg. Chem. 2011, 50, 4842. 3. a) Yang, W.; Yi, F.; Tian, T.; Tian, W.; Sun, Z. Crystal Growth & Design 2014, 14, 1366. b) Yang, W.; Tian, T.; Wu, H.; Pan, Q.; Dang, S.; Sun, Z. Inorg. Chem. 2013, 52, 2736. c) Wu, H.; Yang, W.; Sun, Z. Crystal Growth & Design 2012, 12, 4669. d) Yu, Y.; Zhan, W.; AlbrechtSchmitt, T. E. Inorg. Chem. (Washington, DC, U. S.) 2008, 47, 9050. e) Yu, Y.; Zhan, W.; Albrecht-Schmitt, T. E. Inorg. Chem. (Washington, DC, U. S.) 2007, 46, 10214.

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4. a) Adelani, P. O.; Albrecht-Schmitt, T. Inorg. Chem. 2011, 50, 12184. b) Adelani, P. O.; Albrecht-Schmitt, T. E. Angew. Chem. Int. Ed Engl. 2010, 49, 8909. c) Shvareva, T. Y.; Almond, P. M.; Albrecht-Schmitt, T. E. J. Solid State Chem., 2005, 178, 499. d) Shvareva, T. Y.; Sullens, T. A.; Shehee, T. C.; Albrecht-Schmitt, T. E. Inorg. Chem. 2005, 44, 300. e) Shvareva, T. Y.; Skanthkumar, S.; Soderholm, L.; Clearfield, A.; Albrecht-Schmitt, T. E. Chem. Mater. 2007, 19, 132. f) Ok, K. M.; Baek, J.; Halasyamani, P. S. Inorg. Chem. 2006, 45, 10207. 5. a) Grohol, D.; Blinn, E. L. Inorg. Chem. 1997, 36, 3422. b) Pozas-Tormo, R.; Moreno-Real, L.; Martinez-Lara, M.; Rodriguez-Castellon, E. Can. J. Chem. 1986, 64, 35. c) Dorhout, P. K.; Rosenthal, G. L.; Ellis, A. B. Solid State Ionics 1989, 32–33, Part 1, 50. 6. a) S. Obbade, S.; Duvieubourg, L.; Dion, C.; Abraham, F. J. Solid State Chem. 2007, 180, 866. b) Obbade, S.; Dion, C.; Saadi, M.; Abraham, F. J. Solid State Chem. 2004, 177, 1567. c) Johnson, C. H.; Shilton, M. G.; Howe, A. T. J. Solid State Chem. 1981, 37, 37. 7. Sykora, R.E.; Albrecht-Schmitt, T. E. Inorg. Chem. 2003, 47, 2179. 8. a) Yeon, J.; Smith, M. D.; Sefat, A. S.; zur Loye, H. Inorg. Chem. 2013, 52, 2199. b) Mougel, V.; Chatelain, L.; Pécaut, J.; Caciuffo, R.; Colineau, E.; Griveau, J.; Mazzanti, M. Nat Chem

2012, 4, 1011. c) Rinehart, J. D.; Harris, T. D.; Kozimor, S. A.; Bartlett, B. M.; Long, J. R. Inorg. Chem. (Washington, DC, U. S.) 2009, 48, 3382. d) Kozimor, S. A.; Bartlett, B. M.; Rinehart, J. D.; Long, J. R. J. Am. Chem. Soc. 2007, 129, 10672. e) Mörtl, K. P.; Sutter, J.; Golhen, S.; Ouahab, L.; Kahn, O. Inorg. Chem. 2000, 39, 1626. 9. Burns, P. C. Can. Mineral. 2005, 43, 1839. 10. a) Grohol, D.; Clearfield, A. J. Am. Chem. Soc. 1997, 119, 9301. b) Grohol, D.; Clearfield, A. J. Am. Chem. Soc. 1997, 119, 4662. c)

Grohol, D.; Subramanian, M. A.; Poojary, D. M.;

Clearfield, A. Inorg. Chem. 1996, 35, 5264. 11. Adelani, P. O.; Cook, N. D.; Babo, J.-M.; Burns, P. C. Inorg. Chem. 2014, 53, 4169. 12. a) Sheldrick, G. M. Acta Crystallogr. 2008, A64, 211. b) Palmer, D. CrystalMaker for Windows, 2.7.7; CrystalMaker Software Limited: Oxfordshire, England, 2009. ACS Paragon Plus Environment

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13. (a) Burns, P. C.; Ewing, R. C.; Hawthorne, F. C.; Can. Mineral. 1997, 35, 1551. (b) Brese, N. E.; O’Keeffe, M. Acta Crystallogr. 1991, B47, 192. 14. a) Adelani, P. O.; Albrecht-Schmitt, T. Crystal Growth & Design 2012, 12, 5800. b) Adelani, P. O.; Albrecht-Schmitt, T. E. Journal of Solid State Chemistry 2012, 192, 377. c) Adelani, P. O.; Albrecht-Schmitt, T. E. Journal of Solid State Chemistry 2011, 184, 2368. d) Adelani, P. O.; Oliver, A. G.; Albrecht-Schmitt, T. Crystal Growth & Design 2011, 11, 1966. e) Adelani, P. O.; Albrecht-Schmitt, T. Crystal Growth & Design 2011, 11, 4227. f) Adelani, P. O.; AlbrechtSchmitt, T. Inorg. Chem. 2009, 48, 2732. 15. (a) Frisch, M.; Cahill, C. L. Dalton Trans. 2006, 39, 4679. (b) Cahill, C. L.; de Lill, D. T.; Frisch, M. CrystEngComm. 2007, 9, 15. 16. (a) Marino, N.; Armentano, D.; De Munno, G.; Cano, J.; Lloret, F.; Julve, M. Inorg. Chem.

2012, 51, 4323. (b) Demunno, G.; Julve, M.; Lloret, F.; Faus, J.; Verdaguer, M.; Caneschi, A. Inorg. Chem. 1995, 34, 157. (c) Demunno, G.; Julve, M.; Lloret, F.; Cano, J.; Caneschi, A. Inorg. Chem. 1995, 34, 2048. (d) Demunno, G.; Julve, M.; Nicolo, F.; Lloret, F.; Faus, J.; Ruiz, R.; Sinn, E. Angewandte Chemie-International Edition in English 1993, 32, 613. 17. (a) Thuery, P. Inorg. Chem. 2013, 52, 435. (b) Thuery, P.; Riviere, E. Dalton Trans. 2013, 42, 10551.

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“For Table of Contents Use Only”

Use of 2,2-Bipyrimidine for the Preparation of UO22+─3d Diphosphonates Pius O. Adelani1, Nathaniel D. Cook1, and Peter C. Burns*1,2

Three new multidimensional bimetallic UO22+─3d complexes were crystallized in high yield under mild hydrothermal reactions in the presence of bipym. The bipym moiety stabilizes the 3d metal centers yielding a variety of 3d-uranyl diphosphonate complexes with interesting three-dimensional networks. A nickel metal center with similar coordination environment as 2 had been reported earlier, whereas the incorporation of manganese and zinc metal centers in 1 and 3, respectively, are remarkable.

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