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1.
The symmetry, structure and formation mechanism of the structurally self‐complementary { Pd84 } = [Pd84O42(PO4)42(CH3CO2)28]70? wheel is explored. Not only does the symmetry give rise to a non‐closest packed structure, the mechanism of the wheel formation is proposed to depend on the delicate balance between reaction conditions. We achieve the resolution of gigantic polyoxopalladate species through electrophoresis and size‐exclusion chromatography, the latter has been used in conjunction with electrospray mass spectrometry to probe the formation of the ring, which was found to proceed by the stepwise aggregation of {Pd6}? = [Pd6O4(CH3CO2)2(PO4)3Na6?nHn]? building blocks. Furthermore, the higher‐order assembly of these clusters into hollow blackberry structures of around 50 nm has been observed using dynamic and static light scattering.  相似文献   

2.
The asymmetric unit of the title compound, dipotassium bis[hexaaquanickel(II)] tris(μ2‐methylenediphosphonato)tripalladium(II) hexahydrate, K2[Ni(H2O)6]2[Pd3{CH2(PO3)2}3]·6H2O, consists of half a {[Pd{CH2(PO3)2}]3}6− anion [one Pd atom (4e) and a methylene C atom (4e) occupy positions on a twofold axis] in a rare `handbell‐like' arrangement, with K+ and [Ni(H2O)6]2+ cations to form the neutral complex, completed by three solvent water molecules. The {[Pd{CH2(PO3)2}]3}6− units exhibit close Pd...Pd separations of 3.0469 (4) Å and are packed via intermolecular C—H...Pd hydrogen bonds. The [KO9] and [NiO6] units are assembled into sheets coplanar with (011) and stacked along the [100] direction. Within these sheets there are [K4Ni4O8] and [K2Ni2O4] loops. Successive alternation of the sheets and [Pd{CH2(PO3)2}]3 units parallel to [001] produces the three‐dimensional packing, which is also supported by a dense network of hydrogen bonds involving the solvent water molecules.  相似文献   

3.
Polynuclear Pd(II) and Ni(II) complexes of macrocyclic polyamine 3,6,9,16,19,22‐hexaazatricyclo[22.2.2.211,14]‐triaconta 11,13,24,26(l),27,29‐hexaene (L) in solution were investigated by electrospray ionization mass spectrometry (ESIMS). For methanol solution of complexes M2LX4 (M = Pd(II) and Ni(II), X= Cl and I), two main clusters of peaks were observed which can be assigned to [M2LX3]+ and [M2LX2]2+. When Pd2LCl4 was treated with 2 or 4 mol of AgNO3, it gave rise formation of Pd2LCl2 (NO3)2 · H2O and [Pd2L(H2O)m(NO3)n](4‐n)+, respectively. ESMS spectra show that the dissociation of the former in the ionization process gave peaks of [Pd2LCl2]2+ and [(Pd2LCl2)NO3]+, while dissociation of the later gave the peaks of [Pd2L(CH3CO2)2]2+ and [Pd2L(CH3CO2)2](NO3) + in the presence of acetic acid. Similar species were observed for Pd2LI4 when treated with 4 mol of AgNO3. When [Pd2L · (H2O)m(NO3)n](4‐n)+ reacted with 2 mol of oxalate anions at 40°C, [Pd4L2(C2O4)2(NO3)2]2+ and [Pd4L2(C2O4)2 (NO3)]3+ were detected. This implies the formation of square‐planar molecular box Pd4L2(C2O4)2(NO3)4 in which C2O4? may act as bridging ligands as confirmed by crystal structure analysis. The dissociation form and the stability of complex cations in gaseous state are also discussed. This work provides an excellent example of the usefulness of ESIMS in the identification of metal complexes in solution.  相似文献   

4.
Tetrakis(p‐tolyl)oxalamidinato‐bis[acetylacetonatopalladium(II)] ([Pd2(acac)2(oxam)]) reacted with Li–C≡C–C6H5 in THF with formation of [Pd(C≡C–C6H5)4Li2(thf)4] ( 1a ). Reaction of [Pd2(acac)2(oxam)] with a mixture of 6 equiv. Li–C≡C–C6H5 and 2 equiv. LiCH3 resulted in the formation of [Pd(CH3)(C≡C–C6H5)3Li2(thf)4] ( 2 ), and the dimeric complex [Pd2(CH3)4(C≡C–C6H5)4Li4(thf)6] ( 3 ) was isolated upon reaction of [Pd2(acac)2(oxam)] with a mixture of 4 equiv. Li–C≡C–C6H5 and 4 equiv. LiCH3. 1 – 3 are extremely reactive compounds, which were isolated as white needles in good yields (60–90%). They were fully characterized by IR, 1H‐, 13C‐, 7Li‐NMR spectroscopy, and by X‐ray crystallography of single crystals. In these compounds Li ions are bonded to the two carbon atoms of the alkinyl ligand. 1a reacted with Pd(PPh3)4 in the presence of oxygen to form the already known complexes trans‐[Pd(C≡C–C6H5)2(PPh3)2] and [Pd(η2‐O2)(PPh3)2]. In addition, 1a is an active catalyst for the Heck coupling reaction, but less active in the catalytic Sonogashira reaction.  相似文献   

5.
The synthesis and crystal structure (at 100 K) of the title compound, Cs[Fe(C11H13N3O2S2)2]·CH3OH, is reported. The asymmetric unit consists of an octahedral [FeIII(L)2] fragment, where L2− is 3‐ethoxysalicylaldehyde 4‐methylthiosemicarbazonate(2−) {systematic name: [2‐(3‐ethoxy‐2‐oxidobenzylidene)hydrazin‐1‐ylidene](methylamino)methanethiolate}, a caesium cation and a methanol solvent molecule. Each L2− ligand binds through the thiolate S, the imine N and the phenolate O atoms as donors, resulting in an FeIIIS2N2O2 chromophore. The O,N,S‐coordinating ligands are orientated in two perpendicular planes, with the O and S atoms in cis positions and the N atoms in trans positions. The FeIII cation is in the low‐spin state at 100 K.  相似文献   

6.
The title compound, hexapotassium octairon(II,III) dodecaphosphonate, exhibiting a two‐dimensional structure, is a new mixed alkali/3d metal phosphite. It crystallizes in the space group Rm, with two crystallographically independent Fe atoms occupying sites of m (Fe1) and 3m (Fe2) symmetry. The Fe2 site is fully occupied, whereas the Fe1 site presents an occupancy factor of 0.757 (3). The three independent O atoms, one of which is disordered, are situated on a mirror and all other atoms are located on special positions with 3m symmetry. Layers of formula [Fe3(HPO3)4]2− are observed in the structure, formed by linear Fe3O12 trimer units, which contain face‐sharing FeO6 octahedra interconnected by (HPO3)2− phosphite oxoanions. The partial occupancy of the Fe1 site might be described by the formation of two [Fe(HPO3)2] layers derived from the [Fe3(HPO3)4]2− layer when the Fe1 atom is absent. Fe2+ is localized at the Fe1 and Fe2 sites of the [Fe3(HPO3)4]2− sheets, whereas Fe3+ is found at the Fe2 sites of the [Fe(HPO3)2] sheets, according to bond‐valence calculations. The K+ cations are located in the interlayer spaces, between the [Fe3(HPO3)4]2− layers, and between the [Fe3(HPO3)4]2− and [Fe(HPO3)2] layers.  相似文献   

7.
The C3‐symmetric chiral propylated host‐type ligands (±)‐tris(isonicotinoyl)‐tris(propyl)‐cyclotricatechylene ( L1 ) and (±)‐tris(4‐pyridyl‐4‐benzoxy)‐tris(propyl)‐cyclotricatechylene ( L2 ) self‐assemble with PdII into [Pd6L8]12+ metallo‐cages that resemble a stella octangula. The self‐assembly of the [Pd6( L1 )8]12+ cage is solvent‐dependent; broad NMR resonances and a disordered crystal structure indicate no chiral self‐sorting of the ligand enantiomers in DMSO solution, but sharp NMR resonances occur in MeCN or MeNO2. The [Pd6( L1 )8]12+ cage is observed to be less favourable in the presence of additional ligand, than is its counterpart, where L=(±)‐tris(isonicotinoyl)cyclotriguaiacylene ( L1 a ). The stoichiometry of reactant mixtures and chemical triggers can be used to control formation of mixtures of homoleptic or heteroleptic [Pd6L8]12+ metallo‐cages where L= L1 and L1 a .  相似文献   

8.
The title complex, [Li2(D2O)6][Li(C9H27SSiO3)2]2·2D2O, is the first compound with an S—M bond (M = alkali metal) within an unusual type of lithate anion, [Li(SR)2] {where R is Si[OC(CH3)3]3}. There is a centre of symmetry located in the middle of the Li2O2 ring of the cation. All Li atoms are four‐coordinate, with LiO4 (cations) and LiO2S2 (anions) cores. The singly charged [Li(SR)2] anions are well separated from the doubly charged [Li2(D2O)6]2+ cations; the distance between Li atoms from differently charged ions is greater than 5 Å. Both ion types are held within an extended network of O—D⋯O and O—D⋯S hydrogen bonds.  相似文献   

9.
2‐Phenylethanol, racemic 1‐phenyl‐2‐propanol, and 2‐methyl‐1‐phenyl‐2‐propanol have been pyrolyzed in a static system over the temperature range 449.3–490.6°C and pressure range 65–198 torr. The decomposition reactions of these alcohols in seasoned vessels are homogeneous, unimolecular, and follow a first‐order rate law. The Arrhenius equations for the overall decomposition and partial rates of products formation were found as follows: for 2‐phenylethanol, overall rate log k1(s−1)=12.43−228.1 kJ mol−1 (2.303 RT)−1, toluene formation log k1(s−1)=12.97−249.2 kJ mol−1 (2.303 RT)−1, styrene formation log k1(s−1)=12.40−229.2 kJ mol−1(2.303 RT)−1, ethylbenzene formation log k1(s−1)=12.96−253.2 kJ mol−1(2.303 RT)−1; for 1‐phenyl‐2‐propanol, overall rate log k1(s−1)=13.03−233.5 kJ mol−1(2.303 RT)−1, toluene formation log k1(s−1)=13.04−240.1 kJ mol−1(2.303 RT)−1, unsaturated hydrocarbons+indene formation log k1(s−1)=12.19−224.3 kJ mol−1(2.303 RT)−1; for 2‐methyl‐1‐phenyl‐2‐propanol, overall rate log k1(s−1)=12.68−222.1 kJ mol−1(2.303 RT)−1, toluene formation log k1(s−1)=12.65−222.9 kJ mol−1(2.303 RT)−1, phenylpropenes formation log k1(s−1)=12.27−226.2 kJ mol−1(2.303 RT)−1. The overall decomposition rates of the 2‐hydroxyalkylbenzenes show a small but significant increase from primary to tertiary alcohol reactant. Two competitive eliminations are shown by each of the substrates: the dehydration process tends to decrease in relative importance from the primary to the tertiary alcohol substrate, while toluene formation increases. © 1999 John Wiley & Sons, Inc. Int J Chem Kinet 31: 401–407, 1999  相似文献   

10.
2‐Methylideneglutarate mutase is an adenosylcobalamin (coenzyme B12)‐dependent enzyme that catalyses the equilibration of 2‐methylideneglutarate with (R)‐3‐methylitaconate. This reaction is believed to occur via protein‐bound free radicals derived from substrate and product. The stereochemistry of the formation of the methyl group of 3‐methylitaconate has been probed using a `chiral methyl group'. The methyl group in 3‐([2H1,3H]methyl)itaconate derived from either (R)‐ or (S)‐2‐methylidene[3‐2H1,3‐3H1]glutarate was a 50 : 50 mixture of (R)‐ and (S)‐forms. It is concluded that the barrier to rotation about the C−C bond between the methylene radical centre and adjacent C‐atom in the product‐related radical [.CH2CH(O2CC=CH2)CO2] is relatively low, and that the interaction of the radical with cob(II)alamin is minimal. Hence, cob(II)alamin is a spectator of the molecular rearrangement of the substrate radical to product radical.  相似文献   

11.
The title compound, [Cu3(C3H5O2)6(C6H7NO)4]n, is composed of polymeric chains formed by alternating centrosymmetric Cu2(μ‐CH3CH2CO2)4 and Cu(C3H5O2)2(C6H7NO)2 units. These elemental units are linked by two bridging 3‐pyridylmethanol (3PM) ligands. The Cu2(μ‐CH3CH2CO2)4 group presents a centrosymmetric tetra­bridged structure with four synsyn bridging propionate ligands to which two 3PM mol­ecules are bonded (through N), occupying the apical positions of each square‐pyramidal polyhedron around the CuII ions. The remaining mononuclear group is centred around a third CuII ion, which lies on a symmetry centre and is bound to two monodentate propionate groups (through O), two monodentate 3PM mol­ecules (through N) and two bridging 3PM mol­ecules (through O), thus completing a square‐bipyramidal CuO2N2O2 coordination.  相似文献   

12.
《化学:亚洲杂志》2017,12(15):1909-1914
A dodecavanadate, [V12O32]4−, is an inorganic bowl‐type host with a cavity entrance with a diameter of 4.4 Å in the optimized structure. Linear, bent, and trigonal planar anions are tested as guest anions and the formation of host–guest complexes, [V12O32(X)]5− (X=CN, OCN, NO2, NO3, HCO2, and CH3CO2), were confirmed by X‐ray crystallographic analyses and a 51V NMR spectroscopy study. The degree of distortion of the bowl from a regular to an oval shape depends on the type of guest anion. In 51V NMR spectroscopy, all chemical shifts of the host–guest complexes are clearly shifted after guest incorporation. The incorporation reaction rates for OCN, NO2, HCO2, and CH3CO2 are much larger than those of NO3 and halides. The incorporated nonspherical molecular anions in the dodecavanadate host are easily dissociated or exchanged for other anions, whereas spherical halides in the host are preserved without dissociation, even in the presence of the tested anions.  相似文献   

13.
The title compound, (C4H12N)4[Ta6Cl18]Cl, crystallizes in the cubic space group . The crystal structure contains two different types of coordination polyhedra, i.e. four tetrahedral [(CH3)4N]+ cations and one octahedral [(Ta6Cl12)Cl6]3− cluster anion, and one Cl ion. The presence of three different kinds of Cl atoms [bridging (μ2), terminal and counter‐anion] in one mol­ecule makes this substance unique in the chemistry of hexanuclear halide clusters of niobium and tantalum. The Ta6 octahedron has an ideal Oh symmetry, with a Ta—Ta interatomic distance of 2.9215 (7) Å.  相似文献   

14.
Single crystals of oxidephosphates MTi2O2(PO4)2 [M: Fe (dark red), Co (pinkish red), Ni (green)] with edge‐lengths up to 0.4 mm were grown by chemical vapour transport. FeTi2O2(PO4)2 and CoTi2O2(PO4)2 are isotypic to NiTi2O2(PO4)2. The crystal structure of the latter was previously solved from powder data [FeTi2O2(PO4)2 (data for CoTi2O2(PO4)2 and NiTi2O2(PO4)2 in brackets): monoclinic, P21/c, Z = 2, a = 7.394(3) (7.381(6), 7.388(4)) Å, b = 7.396(2) (7.371(5), 7.334(10)) Å, c = 7.401(3) (7.366(6), 7.340(3)) Å, β = 120.20(3) (120.26(6), 120.12(4))°, R1 = 0.0393 (0.0309, 0.0539) wR2 = 0.1154 (0.0740, 0.1389), 2160 (1059, 1564) independent reflections, 75 (76, 77) variables]. The single‐crystal study allowed improved refinement using anisotropic displacement parameters, yielded lower standard deviations for the structural parameters and revealed a small amount of cation disordering. Twinning and cation disordering within the structures are rationalized by a detailed crystallographic classification of the MTi2O2(PO4)2 structure type in terms of group‐subgroup relations. The structure is characterized by a three‐dimensional network of [PO4] tetrahedra and [MIITi2O12] groups formed by face‐sharing of [MIIO6] and [TiO6] octahedra. Electronic absorption spectra of MTi2O2(PO4)2 in the UV/VIS/NIR region show rather large ligand‐field splittings for the strongly trigonally distorted chromophors [MIIO6] (M = Fe, Co, Ni) with interelectronic repulsion parameters beeing slightly smaller than in other phosphates. Interpretation of the spectra within the framework of the angular overlap model reveals a significant second‐sphere ligand field effect of TiIV ions on the electronic levels of the NiII and CoII.  相似文献   

15.
The water‐insoluble title compound, octakis(μ‐acetato‐κ2O:O)­octakis(μ‐nitro­so‐κ2N:O)­octapalladium(II), [Pd8(CH3COO)8(NO)8], was precipitated as a yellow powder from a solution of palladium nitrate in nitric acid by adding acetic acid. Ab initio crystal structure determination was carried out using X‐ray powder diffraction techniques. Patterson and Fourier syntheses were used for atom locations, and the Rietveld technique was used for the final structure refinement. The crystal structure is of a molecular type. The skeleton of the [Pd8(CH3COO)8(NO)8] mol­ecule is con­structed as a tetragonal prism with Pd atoms at the vertices. The eight NO groups are in bridging positions along the horizontal edges of the prism. The N and O atoms of each nitro­so group coordinate two different Pd atoms. The vertical edges present Pd⋯Pd contacts with a short distance of 2.865 (1) Å. These Pd atoms are bridged by a pair of acetate groups in a cis orientation with respect to each other. The complex has crystallographically imposed 4/m symmetry; all C atoms of the acetate groups are on mirror planes. The unique Pd atom lies in a general position and has square‐planar coordination, consisting of three O and one N atom.  相似文献   

16.
A series of the octapalladium chains supported by meso-Ph2PCH2P(Ph)CH2P(Ph)CH2PPh2 (meso-dpmppm) ligands, [Pd8(meso-dpmppm)4(L)2](BF4)4 (L=none ( 1 ), solvents: CH3CN ( 2 a ), dmf ( 2 b ), dmso ( 2 c ), RN≡C: R=Xyl ( 3 a ), Mes ( 3 b ), Dip ( 3 c ), tBu ( 3 d ), Cy ( 3 e ), CH3(CH2)7 ( 3 f ), CH3(CH2)11 ( 3 g ), CH3(CH2)17 ( 3 h )) and [Pd8(meso-dpmppm)4(X)2](BF4)2 (X=Cl ( 4 a ), N3 ( 4 b ), CN ( 4 c ), SCN ( 4 d )), were synthesized by using 2 a as a stable good precursor, and characterized by spectroscopic (IR, 1H and 31P NMR, UV-vis-NIR, ESI-MS) measurements and X-ray crystallographic analyses (for 1 , 2 a , b , 3 a , b , e , f , 4 a – d ). On the basis of DFT calculations on the X-ray determined structure of 2 b ( [2b-Pd8]4+ ) and the optimized models [Pd8(meso-Ph2PCH2P(H)CH2P(H)CH2PH2)4(CH3CN)2]4+ ( [Pd8Ph8]4+ ) and [Pd8(meso-H2PCH2P(H)CH2P(H)CH2PH2)4(CH3CN)2]4+ ( [Pd8H8]4+ ), with and without empirically calculating dispersion force stabilization energy (B3LYP-D3, B3LYP), the formation energy between the two Pd4 fragments is assumed to involve mainly noncovalent interactions (ca. −70 kcal/mol) with four sets of interligand C−H/π interactions and Pd⋅⋅⋅Pd metallophilic one, while electron shared covalent interactions are almost canceled out within the Pd8 chain. All the compounds isolated are stable in solution and exhibit characteristic absorption at ∼900 nm, which is assignable to a spin allowed HOMO to LUMO transition, and shows temperature dependent intensity change with variable absorption coefficients presumably due to coupling with some thermal vibrations. The structures and electronic states of the Pd8 chains are found finely tunable by varying the terminal capping ligands. In particular, theoretical calculations elucidated that the HOMO-LUMO energy gap is systematically related to the central Pd−Pd distance (2.7319(6)–2.7575(6) Å) by two ways with neutral ligands L ( 1 , 2 , 3 ) and with anionic ligands X ( 4 ), which are reflected on the NIR absorption energy of 867–954 nm. The isocyanide terminated Pd8 complexes ( 3 ) further reacted with excess of RNC (6 eq) to afford the Pd4 complexes, [Pd4(meso-dpmppm)2(RNC)2](BF4)2 ( 13 ), and the cyclic voltammograms of 2 a (L=CH3CN), 3 , and 13 (R=Xyl, Mes, tBu, Cy) demonstrated wide range redox behaviors from 2{Pd4}4+ to 2{Pd4}0 through 2{Pd4}2+↔{Pd8}4+, {Pd8}3+, and {Pd8}2+ strings. The oxidized complexes, [Pd4(meso-dpmppm)2(RNC)3](BF4)4 ( 16 ), were characterized by X-ray analyses, and the two-electron reduced chain of [Pd8(meso-dpmppm)4](BF4)2 ( 7 ) was analyzed by spectroscopic and electrochemical techniques and DFT calculations. Reactions of 2 a with 1 equiv. of aromatic linear bisisocyanide (BI) in CH2Cl2 deposited insoluble coordination polymers, {[Pd8(meso-dpmppm)4(BI)](BF4)4}n ( 5 ), and interestingly, they were soluble in acetonitrile, 31P{1H} and 1H DOSY NMR spectra as well as SAXS curves suggesting that the coordination polymers may exist in acetonitrile as dynamically 1D self-assembled coordination polymers comprising ca. 50 units of the Pd8 rod averaged within the timescale.  相似文献   

17.
The title synthesized hypophosphite has the formula V(H2PO2)3. Its structure is based on VO6 octahedra and (H2PO2) pseudo‐tetrahedra. The asymmetric unit contains two crystallographically distinct V atoms and six independent (H2PO2) groups. The connection of the polyhedra generates [VPO6H2]6− chains extended along a, b and c, leading to the first three‐dimensional network of an anhydrous transition metal hypophosphite.  相似文献   

18.
π‐Conjugated organic materials exhibit high and tunable nonlinear optical (NLO) properties, and fast response times. 4′‐Phenyl‐2,2′:6′,2′′‐terpyridine (PTP) is an important N‐heterocyclic ligand involving π‐conjugated systems, however, studies concerning the third‐order NLO properties of terpyridine transition metal complexes are limited. The title binuclear terpyridine CoII complex, bis(μ‐4,4′‐oxydibenzoato)‐κ3O,O′:O′′;κ3O′′:O,O′‐bis[(4′‐phenyl‐2,2′:6′,2′′‐terpyridine‐κ3N,N′,N′′)cobalt(II)], [Co2(C14H8O5)2(C21H15N3)2], (1), has been synthesized under hydrothermal conditions. In the crystal structure, each CoII cation is surrounded by three N atoms of a PTP ligand and three O atoms, two from a bidentate and one from a symmetry‐related monodentate 4,4′‐oxydibenzoate (ODA2−) ligand, completing a distorted octahedral coordination geometry. Neighbouring [Co(PTP)]2+ units are bridged by ODA2− ligands to form a ring‐like structure. The third‐order nonlinear optical (NLO) properties of (1) and PTP were determined in thin films using the Z‐scan technique. The title compound shows a strong third‐order NLO saturable absorption (SA), while PTP exhibits a third‐order NLO reverse saturable absorption (RSA). The absorptive coefficient β of (1) is −37.3 × 10−7 m W−1, which is larger than that (8.96 × 10−7 m W−1) of PTP. The third‐order NLO susceptibility χ(3) values are calculated as 6.01 × 10−8 e.s.u. for (1) and 1.44 × 10−8 e.s.u. for PTP.  相似文献   

19.
In (η6p‐cymene)(difluorophosphinato‐κO){2‐[(1H‐pyrazol‐1‐yl)methyl‐κN2]pyridine‐κN}ruthenium(II) 0.85‐hexafluorophosphate 0.15‐tetrafluoroborate, [Ru(PO2F2)(C10H14)(C9H9N3)](PF6)0.85(BF4)0.15, (I), the [PO2F2] ligand exhibits positional disorder due to one F atom and one O atom sharing the same two positions related by a mirror reflection across the O—P—F plane. The correct composition of this coordinated anion was successfully determined to be [PO2F2] by refining the complex with various tetrahedral anions in which terminal atoms have similar atomic form factors. The noncoordinated counter‐ion is compositionally disordered between [PF6] and [BF4]. The difficulty in determining the correct composition of this anion illustrates the importance of a crystallographer remaining impartial and open to encountering unexpected moieties in the process of elucidating a structure.  相似文献   

20.
The title compound, {[Zn4(C8H4O4)3(OH)2(C12H6N2O2)2]·2H2O}n, has been prepared hydrothermally by the reaction of Zn(NO3)2·6H2O with benzene‐1,4‐dicarboxylic acid (H2bdc) and 1,10‐phenanthroline‐5,6‐dione (pdon) in H2O. In the crystal structure, a tetranuclear Zn4(OH)2 fragment is located on a crystallographic inversion centre which relates two subunits, each containing a [ZnN2O4] octahedron and a [ZnO4] tetrahedron bridged by a μ3‐OH group. The pdon ligand chelates to zinc through its two N atoms to form part of the [ZnN2O4] octahedron. The two crystallographically independent bdc2− ligands are fully deprotonated and adopt μ3‐κOO′:κO′′ and μ4‐κOO′:κO′′:κO′′′ coordination modes, bridging three or four ZnII cations, respectively, from two Zn4(OH)2 units. The Zn4(OH)2 fragment connects six neighbouring tetranuclear units through four μ3‐bdc2− and two μ4‐bdc2− ligands, forming a three‐dimensional framework with uninodal 6‐connected α‐Po topology, in which the tetranuclear Zn4(OH)2 units are considered as 6‐connected nodes and the bdc2− ligands act as linkers. The uncoordinated water molecules are located on opposite sides of the Zn4(OH)2 unit and are connected to it through hydrogen‐bonding interactions involving hydroxide and carboxylate groups. The structure is further stabilized by extensive π–π interactions between the pdon and μ4‐bdc2− ligands.  相似文献   

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