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1.
Zeolite ZIF-8 has been etched with acid to form microporous ZIF-8-E crystals. These were then introduced into a polyethersulfone (PES) membrane matrix to enhance its CO2/N2 separation performance. Open through pores of size about 100 nm formed in the ZIF-8 crystals allow the ingrowth of polyethersulfone chains, ensuring a reduction in the number of nonselective voids, thereby achieving better interaction between ZIF-8-E and PES. As a result, the CO2/N2 separation performance of the ZIF-8-E/PES membrane increased significantly, showing a CO2 permeability of 15.7 Barrer and a CO2/N2 ideal selectivity of 6.5.  相似文献   

2.
A 2-naphthol derivative 2 corresponding to the aromatic ring moiety of neocarzinostatin chromophore was found to degrade proteins under photo-irradiation with long-wavelength UV light without any additives under neutral conditions. Structure–activity relationship studies of the derivative revealed that methylation of the hydroxyl group at the C2 position of 2 significantly suppressed its photodegradation ability. Furthermore, a purpose-designed synthetic tumor-related biomarker, a H2O2-activatable photosensitizer 8 possessing a H2O2-responsive arylboronic ester moiety conjugated to the hydroxyl group at the C2 position of 2 , showed significantly lower photodegradation ability compared to 2 . However, release of the 2 from 8 by reaction with H2O2 regenerated the photodegradation ability. Compound 8 exhibited selective photo-cytotoxicity against high H2O2-expressing cancer cells upon irradiation with long-wavelength UV light.  相似文献   

3.
Reaction of MnSO4 · H2O, 2,2′‐bipyridine (bpy), suberic acid and Na2CO3 in CH3OH/H2O yielded a mixture of [Mn2(H2O)4(bpy)2(C8H12O4)2] · 2 H2O ( 1 ) and [Mn(H2O)2‐ (bpy)(C8H12O4)2/2] · H2O ( 2 ). In both complexes, the Mn atoms are octahedrally coordinated by two N atoms of one bpy ligand and four O atoms of two trans positioned H2O molecules and two suberato ligands (d(Mn–O) = 2.107–2.328 Å; d(Mn–N) = 2.250–2.330 Å). The bis‐monodentate suberato ligands bridge Mn atoms to form dinuclear [Mn2(H2O)4(bpy)2(C8H12O4)2] complex molecules in 1 and 1D [Mn(H2O)2(bpy)(C8H12O4)2/2] chains in 2 . Via the intermolecular hydrogen bondings and π‐π stacking interactions, the dinuclear molecules in 1 are assembled into 2D networks parallel to (100), between which the crystal H2O molecules are sandwiched. The polymeric chains in 2 are linked together by interchain hydrogen bonding and π‐π stacking interactions into 3D networks with the crystal H2O molecules located in tunnels along [010]. Crystal data for 1 : P21/c (no. 14), a = 10.092(1) Å, b = 11.916(2) Å, c = 17.296(2) Å, β = 93.41(1)° and Z = 2. Crystal data for 2 : P21/c (no. 14), a = 11.176(2) Å, b = 9.688(1) Å, c = 37.842(6) Å, β = 90.06(1)° and Z = 8.  相似文献   

4.
The Orientation of the Re2Cl82– Ions in (PPh4)2[Re2Cl8] · 2 L (L = Acetonitrile, Dichloromethane) (PPh4)2[Re2Cl8] · 2 MeCN was obtained in small yields from PPh4Cl and ReCl5 in the presence of Na2S4 or K2S5 in acetontrile. Its crystal structure was determined by X‐ray diffraction. The crystals are nearly isotypic with those of (PPh4)2[Re2Cl8] · 2 CH2Cl2. The PPh4+ ions, the solvent molecules, and the chlorine atoms occupy nearly identical positions in both triclinic structures. Nevertheless, 98% of the Re≡Re groups are differently oriented within the slightly elongated Cl8 cubes surrounding them. The space requirement of the elongated cubes seems to be more important for the orientation than electrostatic forces. The PPh4+ ions form (PPh4+)2 pairs around inversion centers.  相似文献   

5.
Synthesis and Crystal Structure of (PPh4)2[Mo2(S2)2Cl8] · 2 CH3CN and its Topotactic Transformation to (PPh4)2[Mo2(S2)2Cl8] MoS2Cl3 was prepared from molybdenum and S2Cl2 at 200 °C. Its reaction with PPh4Cl in acetonitrile yielded (PPh4)2[Mo2(S2)2Cl8] · 2 CH3CN. In vacuum or upon warming, it loses the acetronitrile without degradation of the crystals. According to the X-ray crystal structure determinations both compounds, with and without acetonitrile, are triclinic. They contain the same [Cl4Mo(μ-S2)2MoCl4]2– ions, in which the Mo atoms are joined by two disulfido groups and an Mo–Mo bond. Details of the crystal packings and their topotactic transformation are given.  相似文献   

6.
The synthesis of the following mixed ligand organotellurium(IV) compounds C8H8Te(S2CNEt2)[(SPPh2)2N] · H2O ( 1 ), C8H8Te(S2CNC5H10)[(SPPh2)2N] ( 2 ), C8H8Te(S2CNC4H8O)[(SPPh2)2N] ( 3 ) and C8H8Te(S2CNC4H8S)[(SPPh2)2N] ( 4 ) was achieved. They were characterized by IR, 1H, 13C, 31P and 125Te NMR, mass spectroscopy, and elemental analyses. The X‐ray crystal structures of 1 , 2 and 4 were determined. The both types of ligands display an asymmetrical chelating coordination mode on interaction with the tellurium atom. When these aniso‐bonded donor atoms are included in the coordination sphere, the tellurium atom exhibit an effective co‐ordination number of seven. The arrangement may be described as 1 : 2 : 2 : 2 coordination with a presumably stereoactive lone‐pair of electrons.  相似文献   

7.
New Compounds of the SrNi2V2O8-Type: BaCo2V2O8 and BaMg2V2O8 For the first time BaCo2V2O8 (A) and BaMg2V2O8 (B) were prepared and investigated by X-ray methods. Space group: D–I41/acd, Z = 8. ((A): a = 12.4441, c = 8.4153 Å; (B): a = 12.4189, c = 8.4657 Å). A and B crystallize with higher symmetry, but they are isotypic with SrNi2V2O8. The differences in crystal chemistry in respect to the BaNi2V2O8-type are discussed.  相似文献   

8.
A new ammonium vanadium tellurate, (NH4)4{(VO2)2[Te2O8(OH)2]}·2H2O ( 1 ) was hydrothermally synthesized and characterized by elemental analyses, IR spectrum, TG analysis, and single crystal X–ray diffraction. Compound 1 crystallizes in the monoclinic system, space group P21/n, a = 7.3843(15) Å, b = 17.111(3) Å, c = 7.3916(15) Å, β = 118.88(3)°, V = 817.9(3) Å3, Z = 2, R1 (I>2σ(I)) = 0.0235, wR2 (all data) = 0.0462. The structure of 1 consists of infinite anionic chains, {(VO2)2[Te2O8(OH)2]}4? which contain octahedral VO6 and TeO5OH units. Each octahedral VO6 and TeO5OH unit is connected by sharing an edge to form V2O10 and Te2O8(OH)2 binuclear units. The V2O10 and Te2O8(OH)2 binuclear units are alternatively connected to one another, creating complete infinite {(VO2)2[Te2O8(OH)2]}4? chains along the c direction. The anionic chains are separated by ammonium cations and water molecules that link the chains through a network of hydrogen bonds. In addition, the structure contains an extended network of O–H·····O hydrogen bonds between the chains.  相似文献   

9.
The {Cr8} metallacrown [CrF(O2CtBu)2]8, containing a F‐lined internal cavity, shows high selectivity for CO2 over N2. DFT calculations and absorption studies support the multiple binding of F‐groups to the C‐center of CO2 (C⋅⋅⋅F 3.190(9)–3.389(9) Å), as confirmed by single‐crystal X‐ray diffraction.  相似文献   

10.
Synthesis, Crystal Structures, and Vibrational Spectra of [(Ph3P)2N]2[(W6Cl )I ] · 2 Et2O · 2 CH2Cl2 and [(Ph3P)2N]2[(W6Cl )(NCS) ] · 2 CH2Cl2 By treatment of [(W6Cl)I]2– with (SCN)2 in dichloromethane at –20 °C the hexaisothiocyanato cluster anion [(W6Cl)(NCS)]2– is formed. X‐ray structure determinations have been performed on single crystals of [(Ph3P)2N]2[(W6Cl)I] · 2 CH2Cl2 · 2 Et2O ( 1 ) (triclinic, space group P1, a = 10.324(5), b = 14.908(3), c = 17.734(8) Å, α = 112.78(2)°, β = 99.13(3)°, γ = 92.02(3)°, Z = 1) and [(Ph3P)2N]2[(W6Cl)(NCS)] · 2 CH2Cl2 ( 2 ) (triclinic, space group P1, a = 11.115(2), b = 14.839(2), c = 17.036(3) Å, α = 104.46(1)°, β = 105.75(2)°, γ = 110.59(1)°, Z = 1). The thiocyanate ligands of 2 are bound exclusively via N atoms with W–N bond lengths of 2.091–2.107 Å, W–N–C angles of 173.1–176.9° and N–C–S angles of 178.1–179.3°. The vibrational spectra exhibit characteristic innerligand vibrations at 2067–2045 (νCN), 879–867 (νCS) and 490–482 (δNCS). Based on the molekular parameters of the X‐ray determination of 1 the vibrational spectra of the corresponding (n‐Bu4N) salt of 1 are assigned by normal coordinate analysis. The valence force constants are fd(WW) = 1.61, fd(WI) = 1.23 and fd(WCl) = 1.10 mdyn/Å.  相似文献   

11.
Gd2OSe2     
Single crystals of digadolinium monooxy­gen diselenide, Gd2OSe2, have been obtained from a KBr flux. The compound is isostructural with the low‐pressure form of Dy2OS2. All atoms lie on the mirror plane of Pnma. The Gd environments are a GdO3Se5 bicapped trigonal prism and a GdOSe5 distorted octahedron. The two coordination polyhedra pack by face‐sharing and edge‐sharing to form a [Gd8/4O4/4Sea8/8‐Sei8/8] fragment, which is the main motif of the structure. These fragments lie in the ac plane and form infinite chains parallel to c through the sharing of Se atoms around atom Gd1. In the a direction, these chains stack through the sharing of an Se atom around atom Gd2, thereby delimiting large pentagonal cavities.  相似文献   

12.
Reaction of [(η-C5H5)NiCo3(CO)9] (5) with 1,3,5,7-cyclooctatetraene or 1,4-(SiMe3)2C8H6, respectively, yields the complexes [Co2Ni(CO)638-C8H6R2)] (R=H, SiMe3) (7a, b). Dramatic modifications of the tetrametallic cluster core and the ligand sphere of 5 to give the trinuclear complex 7 are driven by the preference of the cyclopolyenes for facial (μ38) coordination. The title complexes are the first examples of facial cyclooctatetraene coordination to a heterometallic (Co2Ni) triangle.  相似文献   

13.
On Ba(MgZn)V2O8, BaMn2V2O8, and Ba1/2Sr1/2Ni2V2O8 Ba(Mg, Zn)V2O8 (A), BaMn2V2O8 (B) and Ba1/2Sr1/2Ni2V2O8 (C) were prepared by solid state reactions (A and B) and crystallization from a melt (C) respectively. (A? C) crystallize in the space group: D-I41/acd, Nr. 142. [Lattice constants (A): a = 12.4524(57) Å, c = 8.4408(36) Å; (B): a = 12.5563(14) Å, c = 8.5942(9) Å; (C): a = 12.2248(20) Å, c = 8.3245(15) Å]. (A), (B) and (C) are isotypic to SrNi2V2O8 but showing higher symmetry.  相似文献   

14.
1,1-Diiodo-3,4-benzocyclopentatellurane, C8H8TeI2, was reacted with a series of neutral thioureas, selenoureas, and thiones (L) in tetrahydrofuran in the presence of silver tetrafluoroborate to give dicationic complexes of the type [C8H8Te(L)2][BF4]2. These have been characterized by multinuclear NMR spectroscopy, elemental analysis, and a representative single crystal X-ray structure for the complex with L = tetramethylthiourea. The structure and bonding are discussed and compared with related coordinated cyclopentatelluranes.  相似文献   

15.
Oxalato‐ and Squarato‐Bridged Threedimensional Networks: The Crystal Structures of La2(C2O4)(C4O4)2(H2O)8 · 2.5 H2O and K[Bi(C2O4)2] · 5 H2O The title compounds have been formed by hydrolysis of amino‐ and thioderivatives of squaric acid in the presence of LaIII and BiIII ions. Both compounds are threedimensional coordination polymers in the solid state, as shown by single crystal X‐ray crystallography. In La2(C2O4)(C4O4)2(H2O)8 · 2.5 H2O oxalato‐bridged pairs of LaO9 polyhedra are connected with identical neighbouring polyhedra by squarate ions. In K[Bi(C2O4)2] · 5 H2O each Bi atom is fourfold linked to other Bi atoms by the oxalate ions. The resulting 3D network shows a diamond‐like topology with square‐shaped channels. In both structures the channels are partially filled by water molecules.  相似文献   

16.
Regioselective Ring Opening Reactions of Unifold Unsaturated Triangular Cluster Complexes [M2Rh(μ‐PR2)(μ‐CO)2(CO)8] (M2 = Re2, Mn2; R = Cy, Ph; M2 = MnRe, R = Ph) with Diphosphanes Equimolar amounts of the triangular title compounds and chelates of the type (Ph2P)2Z (Z = CH2, DPPM ; C=CH2, EPP ) react in thf solution at –40 to –20 °C under release of the labile terminal carbonyl ligand attached to the rhodium atom in good yields (70–90%) to ring‐opened unifold unsaturated complexes [MRh(μ‐PR2)(CO)4M(DPPM bzw. EPP)(μ‐CO)2(CO)3] (DPPM: M2 = Re2, R = Cy 1 , Ph 2 ; Mn2, Cy 5 , Ph 6 ; MnRe, Cy 7 . EPP: M2 = Re2, R = Cy 8 ; Mn2, Cy 10 ). Complexes 1 , 2 and 8 react subsequently under minor uptake of carbon monoxide and formation of the valence saturated complexes [ReRh(μ‐PR2)(CO)4M(DPPM bzw. EPP) (CO)6] (DPPM: R = Cy 3 , Ph 4 . EPP: R = Cy 9 ). Separate experiments ascertained that the regioselective ring opening at the M–M‐edge of the title compounds is limited to reactions with diphosphanes chelates with only one chain member and that the preparation of the unsaturated complexes demands relatively good donor ability of both P atoms. As examples for both types of compounds the molecular structures of 8 and 3 have been determined from single crystal X‐ray structure analysis. Additionally all new compounds are identified by means of ν(CO)IR, 1H‐ and 31P‐NMR data. This includes complexes with a modified chain member in 1 and 5 which, after deprotonation reaction to carbanionic intermediates, could be trapped with [PPh3Au]+ cations as rac‐[MRh(μ‐PR2)(CO)4M((Ph2P)2CHAuPPh3)(μ‐CO)2(CO)3] (M2 = Re 17 , Mn 18 ) and products rac‐[MRh(μ‐PR2)(CO)4M((Ph2P)2CHCH2R)(μ‐CO)2(CO)3] (M2 = Re, R = Ph 19 , n‐Bu 21 , Me 23 ; Mn, Ph 20 , n‐Bu 22 , Me 24 ) which result from Michael‐type addition reactions of 8 or 10 with strong nucleophiles LiR.  相似文献   

17.
The inherent tendency of BR fragments to undergo coupling is utilized to predict M2B10H10 and M2@B10H8 complexes (where M = Mn and Fe). Electronic structure analysis of Mn2B10H10 (7) shows that the metal d-orbitals stabilize the interlocked boron wheel structure, forming an unprecedented geometrical pattern with Möbius aromaticity. The two additional electrons in Fe2@B10H10 (8) stabilize a twisted [10]boraannulene structure. The removal of 2H from 7 and 8 leads to the planar structures Mn2@B10H8 (11) and Fe2@B10H8 (10), respectively. The stability of the planar arrangements is due to multicentered (σ + π) bonding, where π-donation occurs from the M2 (M = Fe and Mn) unit to the borocyclic unit. The presence of 10π electrons in M2@B10H8 relates it to naphthalene, having Hückel π-aromaticity. The condensation of naphthalene to graphene in two dimensions suggests the ability to build the different metal boride monolayers FeB5 and Fe2B5, considering Fe2@B10 as the building block, bringing this molecular boron chemistry into the solid state. One of the predicted monolayers, β-Fe2B5, is found to be the global minimum in the planar arrangement based on a USPEX crystal structure search algorithm. Electronic structure analysis further shows that the stabilization mechanism in the molecular building block remains unaltered in the solid state.

The design of (1) Möbius aromatic interlocked boron wheel Mn2B10H10, (2) Hückel aromatic boron analogs of naphthalene (M2@B10H8; M = Mn and Fe), and (3) metal boride monolayers (FeB5 and Fe2B5), creating a molecules to materials continuum.  相似文献   

18.
Li2Sr4Al2Ta2N8O was synthesized from Li3AlN2, Sr(NH2)2, LiN3, and lithium metal as fluxing agent in weld shut tantalum crucibles. Single crystals were obtained as byproduct from reaction with the ampoule material. The crystal structure (P21/n (no. 14), a = 9.4081(19), b = 10.012(2), c = 5.9832(12) Å, β = 93.44(3)°, Z = 2) was solved on the basis of single‐crystal X‐ray diffraction data. Li2Sr4Al2Ta2N8O is built up of vertex sharing AlN4 and TaN4 tetrahedra, forming a BCT‐zeolite type structure with Sr2+ ions and molecular Li2O units incorporated into the voids. Lattice energy calculations (MAPLE) confirmed the electrostatic bonding interactions and the chemical composition.  相似文献   

19.
Relative rate experiments using UV photolysis of F2 or Cl2 have been used to determine rate constant ratios for several hydrofluorocarbon (HFC) reactions with Cl or F atoms and for HFC alkyl radicals with molecular halogens. For mixtures with F2 present, dark reactions are, also, observed which are attributed to thermal dissociation of the F2 to form F atoms. At 296 K, the rate of reaction (1a) [CF2HCH3 + F → CF2CH3 + HF] relative to (1b) [CF2HCH3 + F → CF2HCH2 + HF] is k1a/k1b = 0.73 (±0.13) and is independent of T (= 262–348 K). At 296 K, the ratio of reaction (2a) [CF2HCH2F + F → products] to that of (k1a + k1b) is (k1a + k1b)/k2a = 2.7 (±0.4), and for reaction (2b) [CF3CH3 + F → products] (k1a + k1b)/k2b = 22 ± 12. The temperature dependence (263–365 K) of the rate constant of reaction (3) [CF3CFH2 + Cl → products] relative to reaction (4) [CF3CFClH + Cl → products] is k3/k4(±10%) = 1.55 exp(?300 K/T). For the alkyl radicals formed from HFC 152a (CF2HCH2 and CF2CH3) and from HFC 134a (CF3CFH), rate constants for the reactions with F2 and Cl2 were measured relative to their reactions with O2. The rate constant of reaction (5cl) [CF2CH3 + Cl2 → CF2ClCH3 + Cl] relative to (5o) [CF2CH3 + O2 → CF2(O2)CH3] is k5cl/k5o(±15%) = 0.3 exp(200 K/T). For reaction (5f) [CF2CH3 + F2 → CF3CH3 + F], k5f/k5o(±35%) = 0.23. The ratio for reaction (6f) [CF2HCH2 + F2 → CF2HCH2F + F] relative to (6o) [CF2HCH2 + O2 → CF2HCH2O2] is k6f/k6o(±40%) = 1.23 exp(?730 K/T). The rate constant ratio for reaction (8cl) [CF3CFH + Cl2 → CF3CFClH + Cl] relative to reaction (8o) [CF3CFH + O2 → CF3CFHO2] is k8cl/k8o(±18%) = 0.16 exp(?940 K/T). For reaction (8f) [CF3CFH + F2 → CF3CF2H + F], k8f/k8o(±35%) = 0.6 exp(?860 K/T). © 1993 John Wiley & Sons, Inc.  相似文献   

20.
Amido Complexes of Manganese(II). Syntheses and Crystal Structures of [Mn(NPh2)2(THF)]2 and Na2[Mn(NPh2)4] · 2 C7H8 The silylated amido complex [Mn{N(SiMe3)2}2 · (THF)] reacts in toluene solution with diphenylamine under ligand exchange to form the diphenylamido complex [Mn(NPh2)2(THF)]2 ( 1 ), which forms orange-red columnar crystals. 1 reacts in THF solution with NaN(SiMe3)2 and after crystallization from toluene yellow-orange Na2[Mn(NPh2)4] · 2 C7H8 ( 2 ) is obtained. According to the crystal structure analyses the manganese atoms in 1 (space group P21/c, Z = 2) are linked via the N atoms of two of the NPh2 groups to form centrosymmetric Mn2N2 four-membered rings with Mn–N bonds of almost the same length. 2 (space group I41/a, Z = 4) forms a three-dimensional space-lattice structure, which arises from ”︁inner solvation”︁”︁ of the sodium atoms with the phenyl rings of the NPh2 group.  相似文献   

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