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1.
A new silver organodiphosphonate, [Ag4(O3PCH2CH2PO3)] (1), has been synthesized and characterized by X-ray diffraction, IR, TGA-DSC, electricity measurement and element analysis. 1 crystallizes in the monoclinic space group P2(1)/n (a=6.0115(16) Å, b=8.630(2) Å, c=8.462(2) Å, β=97.693(4)°, Z=2, R1=0.0604, wR2=0.1450). 1 contains one-dimensional channels and a three-dimensional Ag?Ag interacted substructural net. TGA and XRD indicate little weight loss up to 300 °C and little structure change after heated at 170 °C for 2 h, respectively. The grain interior conductivity of 1 increases continuously from 50 to 170 °C. Results of EHT calculations show that under thermal or optical excitation the conductivity of 1 is mainly due to transfer of π antibonding electrons of -PO3 group through O atom to Ag 5s orbital, which also leads to enhancement of Ag?Ag interactions and promotes formation of Ag?Ag substructural net.  相似文献   
2.
Hydrothermal synthesis with MCl2 (M = Fe, Cu, and Zn) and disodium 5-ammonium-1-hydroxypentylidene-1,1-bisphosphonate, (Na+)2[+H3N(CH2)4C(OH)(PO32−)(PO3H)] (Na2HAC5OHP2) or sodium 3-ammonium-1-hydroxypropylidene-1,1-bisphosphonate hydrate, Na+[+H3N(CH2)2C(OH)(PO3H)(PO3H)]·H2O (NaH2PAM·H2O) the sodium salt of pamidronic acid, H3PAM) yielded the one-dimensional (1D) iron, molecular copper and two-dimensional (2D) zinc compounds 1D-{[Fe(μ35-HAC5OHP2)]·H2O}, 1, [Cu(η2-H2AC5OHP2)2], 2, 2D-{[Zn257-AC5OHP2)Cl], 3, and 2D-{[Zn(μ23-H2PAM)2], 4, respectively. The bisphosphonate ligand bridges (μn) between 25 metal atoms and uses 27 oxygen donor atoms towards metal coordination (ηn). The zwitterionic nature of the now bis- or tetrakis-deprotonated ammonium–bisphosphonate is retained in the metal complexes. From the reaction of NiCl2 and Na2HAC5OHP2 the zwitterionic 5-ammonium-1-hydroxypentylidene-1-phosphonic acid, +H3N(CH2)4CH(OH)PO3H, 5 was obtained as a product of the ligand P–C bond hydrolysis. Adjacent strands, molecules or layers in 14, respectively are organized through the Coulomb attraction between the positive ammonium group and the negative phosphonate groups, supported by hydrogen-bonding. Each protic H atom on the C–OH, NH3+ and –PO3H group is involved in charge-assisted hydrogen-bonding. The ammonium-pentylidene groups act as hydrophobic separators between the hydrophilic units with the polar M{C(OH)(PO3)2} and {NH3} units. Bond valence sum calculations support the Fe(II) oxidation state in 1, which was experimentally determined from a quantitative polarographic Fe(II)/Fe(III) speciation analysis as well as a temperature variable magnetic study.  相似文献   
3.
4.
A novel one-pot protocol for the synthesis of symmetrical dinucleoside tri-, tetra-, and pentaphosphates, and their phosphonate analogs simply from nucleoside 5′-phosphoropiperidates has been developed by utilizing 4,5-dicyanoimidazole-promoted tandem P–O coupling reactions.  相似文献   
5.
Thirteen nucleoside 5′-triphosphates (NTPs) and their β,γ-bridging oxygen-modified analogs (β,γ-CX2-NTPs, X = H, F, Cl, and Br) have been efficiently synthesized from nucleoside 5′-phosphoropiperidates with 4,5-dicyanoimidazole as the activator. A high-yielding and chromatography-free protocol for the preparation of both natural and base-modified nucleoside 5′-phosphoropiperidates from the corresponding nucleoside 5′-phosphates was also developed.  相似文献   
6.
Hydrothermal reaction of N-methyl-iminobis(methylenephosphonic acid), CH3N(CH2PO3H2)2, (H4L) with copper(II) acetate afforded a new layered Cu(II) amino diphosphonate, Cu3(H2O)2(HL)2?·?2H2O (1). Compound 1 was studied by IR spectroscopy, TGA/DTA data, and X-ray diffraction (XRD) techniques. The XRD patterns are the same for the hydrated and the dehydrated complexes. A single-crystal X-ray crystallographic determination reveals copper in two different coordination environments. Cu1 has a distorted elongated tetragonal octahedral geometry, whereas Cu2 has a square-pyramidal distorted geometry. The HL trianion is a pentadentate ligand with a deprotonated nitrogen atom and two oxygen atoms of each phosphonate binding to copper. Hydrogen bonds between lattice water molecules in interlayer spaces and the non-coordinated phosphonate oxygen atoms as well as water ligands leads to a 3-D supramolecular network structure.  相似文献   
7.
A hydrothermal reaction of a mixture of ZnO, HCl, ethylenediphosphonic acid, ethylenediamine, acetic acid in a water, THF mixture gave rise to a new three‐dimensional zinc ethylenediphosphonate, [NH3(CH2)2NH3][Zn3{O3P(CH2)2}4], I . The structure, determined by single crystal X‐ray diffraction, (monoclinic, space group = C2/c, a = 16.9948(14), b = 6.7383(6), c = 16.8886(14)Å, β = 1113.568(1)°, V = 1772.7(3)Å3, Z = 4, R1 = 0.0227, wR2 = 0.0601), consists of a network of strictly alternating ZnO4 and PO3C tetrahedral units linked through their vertices forming the three‐dimensional structure. The amine molecules occupy the middle of the 8‐membered channels and interact with the framework through the hydrogen bonds. Unlike other zinc diphosphonates, I appear to have close similarity to zinc phosphate structures reported in the literature. To our knowledge, this is the first three‐dimensional zinc diphosphonate prepared in the presence of an organic amine molecule.  相似文献   
8.
The novel aluminum ethylenediphosphonate fluoride, [HN(CH2CH2NH3)3][Al2(O3PCH2CH2PO3)2F2]·H2O (1) (monoclinic, P21/n, a=12.145(4) Å, b=9.265(3) Å, c=20.422(6) Å, β=104.952(4)°, Z=3, R1=0.092, wR2=0.196) has been synthesized by solvothermal methods in the presence of tris(2-aminoethyl)amine and its structure determined using single microcrystal X-ray diffraction data. Compound 1 is a one-dimensional extended chain structure composed of well-separated anionic [Al2(O3PCH2CH2PO3)2F2]4− rods containing helical chains of corner-shared cis-AlO4F2 octahedra at their core. The charge-compensating tris(2-aminoethyl)ammonium cations separate the anionic [Al2(O3PCH2CH2PO3)2F2]4− rods that contain either left- or right-handed helical chains. The incorporation of the organic components into this hybrid material has aided the adoption of one-dimensionality by the compound and defined the pitch of the helical AlO4F chain.  相似文献   
9.
Two novel coordination polymers, [Cu(H2L)(bipy)(H2O)2] · H2O ( 1 ) and [Ni2(H2L)(bipy)2.5(H2O)6] · (H2L) · 7H2O ( 2 ) with the V‐shaped diphosphonate ligand (2,4,6‐trimethyl‐1,3‐phenylene)bis(methylene)diphosphonic acid (H4L) were synthesized via hydrothermal reactions in the presence of auxiliary ligand 4,4′‐bipyridine. Their structures were determined by single‐crystal X‐ray diffraction and further characterized by elemental analysis, infrared spectroscopy (IR), and thermogravimetric analysis (TGA). Compound 1 crystallizes in the Pnma space group and compound 2 crystallizes in the P21212 space group. They display square‐grid layer and bilayer two‐dimensional network, respectively.  相似文献   
10.
Two novel gallium diphosphonates, (C5H5N)Ga3F(O3PC2H4PO3)2 (I) (triclinic, P-1, a=8.2880(12) Å, b=11.7197(16) Å, c=11.7601(17) Å, α=71.589(3)°, β=70.577(3)°, γ=77.313(3)°, V=1013.7(2) Å3, Z=2, R1=0.0352, wR2=0.0980) and (C5H5NH)2[Ga4F2(O3PC2H4PO3)3] (II) (triclinic, P-1, a=8.670(4) Å, b=9.742(3) Å, c=10.406(2) Å, α=81.44(3)°, β=65.83(5)°, γ=67.16(3)°, V=739.0(4) Å3, Z=2, R1=0.0600, wR2=0.1495) have been synthesised by solvothermal methods in the presence of pyridine and their structures determined using single-crystal X-ray diffraction data. Both compounds I and II are composed of various Ga-centered polyhedra and ethylenediphosphonate groups that link together to form framework materials with one- and two-dimensional channel systems, respectively. The two structures are formed in the presence of structure-directing pyridine molecules that are directly bound to some of the Ga atoms in I, and are protonated as pyridinium cations in II. Compounds I has a charge-neutral framework, while compound II has an anionic framework. Both materials provide rare examples of organically structure-directed framework metal diphosphonate materials.  相似文献   
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