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1.
Dioxobis(pyridine‐2‐thiolate‐N, S)molybdenum(VI) (MoO2(Py‐S)2), reacts with of 4‐methylpyridine (4‐MePy) in acetonitrile, by slow diffusion, to afford the title compound. This has been characterized by elemental analysis, IR and 1H NMR spectroscopy. The X‐ray single crystal structure of the complex is described. Structural studies reveal that the molecular structure consists of a β‐Mo8O26 polyanion with eight MoO6 distorted edge‐shared octahedra with short terminal Mo–O bonds (1.692–1.714 Å), bonds of intermediate length (1.887–1.999 Å) and long bonds (2.150–2.473 Å). Two different types of hydrogen bonds have been found: N–H···O (2.800–3.075 Å) and C–H···O (3.095–3.316 Å). The presence of π–π stacking interactions and strong hydrogen bonds are presumably responsible for the special disposition of the pyridinic rings around the polyanion cluster.  相似文献   

2.
Self‐assembly of the rigid organic ligand 2‐propyl‐4,5‐dicarboxy‐1H‐imidazole ( L ) with different metal ions (Zn2+, Ni2+, Cu2+, Cd2+) led to four new complexes, namely, [M( L )(phen)] [M = Zn ( 1 ); Ni ( 2 ); Cd ( 3 )] and [Cu( L )( 4 )] (phen = 1,10‐phenanthroline). Their structures were determined by single‐crystal X‐ray diffraction analyses, and they were further characterized by elemental analysis, IR spectroscopy, and thermogravimetric analysis. Whereas compounds 1 , 2 , and 3 are discrete units, hydrogen‐bonding interactions play a vital role in these complexes. Compounds 1 and 2 form one‐dimensional (1D) and two‐dimensional (2D) structures through hydrogen‐bondinginteractions with helical character. In 1 , the hydrogen bonds (O–H ··· O) alternately bridge the MII cations of the discrete units to form a one‐dimensional (1D) infinite helical chain. Complex 2 forms a 2D helical layer through parallel hydrogen bonds (N/O–H ··· O/N) between two adjacent helical chains. In 3 , the hydrogen bonds (N–H ··· O) connect adjacent discrete units into a ten‐membered ring with extension into a one‐dimensional double‐chain supramolecular structure. Complex 4 is a two‐dimensional gridlike (4,4) topological layer which is extended to a 3D network by hydrogen bonding. The solid‐state fluorescence spectrum of complex 3 was determined.  相似文献   

3.
Two sulfato CuII complexes [Cu2(bpy)2(H2O)(OH)2(SO4)]· 4H2O ( 1 ) and [Cu(bpy)(H2O)2]SO4 ( 2 ) were synthesized and structurally characterized by single crystal X—ray diffraction. Complex 1 consists of the asymmetric dinuclear [Cu2(bpy)2(H2O)(OH)2(SO4)] complex molecules and hydrogen bonded H2O molecules. Within the dinuclear molecules, the Cu atoms are in square pyramidal geometries, where the equatorial sites are occupied by two N atoms of one bpy ligand and two O atoms of different μ2—OH groups and the apical position by one aqua ligand or one sulfato group. Through intermolecular O—H···O and C—H···O hydrogen bonds and intermolecular π—π stacking interactions, the dinuclear complex molecules are assembled into layers, between which the hydrogen bonded H2O molecules are located. The Cu atoms in 2 are octahedrally coordinated by two N atoms of one bpy ligand and four O atoms of two H2O molecules and two sulfato groups with the sulfato O atoms at the trans positions and are bridged by sulfato groups into 1[Cu(bpy)(H2O)2(SO4)2/2] chains. Through the interchain π—π stacking interactions and interchain C—H···O hydrogen bonds, the resulting chains are assembled into bi—chains, which are further interlinked into layers by O—H···O hydrogen bonds between adjacent bichains.  相似文献   

4.
A novel 1D polymeric lead(II) complex containing the first Pb2‐(μ‐N3)2 motif, [Pb(phen)(μ‐N3)(μ‐NO3)]n (phen = 1,10‐phenanthroline), has been synthesized and characterized. The single‐crystal X‐ray data showed the coordination number of Pb2+ ions to be eight (PbN4O4) with the Pb2+ ions having “stereo‐chemically active” electron lone pairs; the coordination sphere is hemidirected. The chains interact with each other via π‐π interactions to create a 3D framework.  相似文献   

5.
A novel 1D PbII coordination polymer containing Pb2‐(μ‐N3)2 unit [Pb(dmp)(N3)2]n (dmp =  2,9‐dimethyl‐1,10‐phenanthroline) has been prepared and characterized. Single‐crystal X‐ray diffraction analyses show that the coordination number for PbII ions is six, PbN6, with “stereochemically active” electron lone pairs and the coordination sphere being hemidirected. The single‐crystal X‐ray data show the chains interact with each other through the π–π stacking interactions, which create a 3D framework. The structure of title complex has been optimized by density functional theory. Structural parameters and IR spectra for the complex are in agreement with the crystal structure.  相似文献   

6.
The reaction of ZnII nitrate with maleic acid (H2mal) / fumaric acid (H2fum) and 4,4′‐dipyridyl disulfide (4‐pds) resulted under same conditions in two distinct interpenetrated compounds, namely [Zn(4‐dps)2(H2O)2]·2Hmal ( 1 ) and [Zn(4‐dps)(fum)] ( 2 ). In 1 , Hmal anion adopts bridging mode based on hydrogen bonding, affording a 2‐fold parallel interpenetrated 3D→3D α‐Po net hydrogen‐bonded framework, in which 1D double‐stranded chains are formed, and then extended to a 3D supramolecular architecture combining second‐sphere hydrogen‐bonded interactions. For 2 , fum dianion takes on bis‐dentate bridging coordination fashion, furnishing a 2‐fold interpenetrated 2D→2D (4,4) layered coordination network, in which the tetrahedral ZnII atoms are interlinked by 4‐dps and fum. Additionally, the compound 2 shows strong fluorescence in the solid state at room temperature.  相似文献   

7.
A single‐strand arylene–vinylene precursor containing four phenylene and three naphthylene units linked together with six vinylene spacers undergoes helical folding via sextuple photocyclization to give a [16]helicene core in a single step. The phenylene and naphthylene units are arranged in the precursor such that unfavorable side reactions (anthracene or benzoperylene formation) are avoided, and this is the key to the success of the one‐step synthesis of [16]helicene, which is the longest [n]helicene that has been synthesized to date.  相似文献   

8.
Acetonitrile and [FXeOXe‐ ‐ ‐FXeF][AsF6] react at ?60 °C in anhydrous HF (aHF) to form the CH3CN adduct of the previously unknown [XeOXe]2+ cation. The low‐temperature X‐ray structure of [CH3CN‐ ‐ ‐XeOXe‐ ‐ ‐NCCH3][AsF6]2 exhibits a well‐isolated adduct‐cation that has among the shortest Xe?N distances obtained for an sp‐hybridized nitrogen base adducted to xenon. The Raman spectrum was fully assigned by comparison with the calculated vibrational frequencies and with the aid of 18O‐enrichment studies. Natural bond orbital (NBO), atoms in molecules (AIM), electron localization function (ELF), and molecular electrostatic potential surface (MEPS) analyses show that the Xe?O bonds are semi‐ionic whereas the Xe?N bonds may be described as strong electrostatic (σ‐hole) interactions.  相似文献   

9.
A simple method is reported for the preparation of double‐helical structures through a series of achiral random and block copolymers poly(styrene‐co‐4‐vinylbenzyl triazolylmethyl methylthymine) (PS‐co‐PVBT) with various T units on the side chains through click reactions of poly(styrene‐co‐4‐vinylbenzyl azide) (PS‐co‐PVBN3) with propargyl thymine (PT) and also the synthesis of the A‐appended pyrene derivative (A‐Py) through click chemistry. This double‐helical structure is observed from achiral random‐coil polystyrene (PS) main chains, stabilized through the combination of multiple A–T hydrogen bonds, and π–π stacking between pyrene units and single‐walled carbon nanotubes (SWCNTs).

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10.
The reaction of CuI with 2,3‐diphenylquinoxaline ( L ) in 1:1 mole proportion in CH3CN/THF afforded the dinuclear complex [CuI( L )]2, 1 , whereas the reactions of MX2 (M = Cu; Hg) with L in 1:2 mole proportion in CH3OH gave the mononuclear complexes CuX2( L )2 (X = Cl, 2 ; Br, 3 ) and HgX2( L )2 (X = Cl, 4 ; Br, 5 ). Formulations of all the complexes were determined on the basis of X‐ray crystallography, elemental, IR‐ and emission spectroscopy. X‐ray examination revealed that complex 1 forms the μ,μ‐iodobridged dimer with distorted trigonal planar geometry through coordination of L ligand by one nitrogen atom to the Cu(I) center. The metal centers of complexes 2 and 3 form distorted square planar geometry while those of complexes 4 and 5 form linear geometry. The molecules of these complexes are interlinked through C‐H—π and/or π‐π stacking and anion—π interactions that form the packed structure. All the complexes exhibit emissions which may be tentatively assigned as intraligand (IL) π r? π* transitions.  相似文献   

11.
Two copper(I)‐based frameworks of complexes {[Cu(L)2(ClO4)]?CH3CN}( 2 ) and {[Cu(L)(ClO4)]? 2CH3CN} ( 3 ) (L = 1,3,5‐tris(4‐pyridylethynyl) benzene) were produced by reacting [Cu(MeCN)4(ClO4)] with different amounts of a ligand (L) using a hydrothermal method at temperatures of up to 130°C. The nitrogen atoms in the pyridine moieties of the ligand coordinate to the Cu(I) ion. The charge on the Cu(I) ion can be stabilized by extending the degree of conjugation in the system and by taking advantage of its highly symmetrical structure. The large degree of conjugation also supports numerous π–π interactions in the framework.  相似文献   

12.
The reaction of CuCl2 · 2 H2O, 1,10‐phenanthroline (phen), suberic acid and Na2CO3 in a CH3CN–H2O solution yielded blue needle‐like crystals of [Cu2(phen)2(C8H12O4)2] · 3 H2O. The crystal structure (monoclinic, P21/n, a = 10.756(2) Å, b = 9.790(2) Å, c = 18.593(4) Å, β = 91.15(3)°, Z = 2, R = 0.043, wR2 = 0.1238) consists of suberato‐bridged [Cu2(phen)2(C8H12O4)4/2] layers and hydrogen bonded H2O molecules. The Cu atoms are coordinated by two N atoms from one bidentate chelating phen ligand and three carboxyl O atoms from different suberato ligands to form distorted [CuN2O3] square‐pyramids with one carboxyl O atom at the apical position (d(Cu–N) = 2.017(2), 2.043(3) Å, basal d(Cu–O) = 1.936(2), 1.951(2) Å and axial d(Cu–O) = 2.389(2) Å). Two [CuN2O3] square‐pyramids are condensed via a common O–O edge to a centrosymmetric [Cu2N4O4] dimer with the Cu…Cu distance of 3.406(1) Å indicating no interaction between Cu atoms. The resultant [Cu2N4O4] dimers are interlinked by the tridentate suberato ligands to form [Cu2(phen)2(C8H12O4)4/2] layers parallel to (101). These are assembled via π‐π stacking interactions into 3D network with H2O molecules in the tunnels extending in the [010] direction.  相似文献   

13.
Three coordination polymers, {[Cd(3‐bpd)2(NCS)2]×C2H5OH}n ( 1 ), {[Cd(3‐bpd)(dpe)(NO3)2]×(3‐bpd)}2 ( 2 ), {[Cd(dpe)2(NCS)2]×3‐bpd×2H2O}n ( 3 ) (3‐bpd = 1,4‐bis(3‐pyridyl)‐2,3‐diaza‐1,3‐butadiene; dpe = 1,2‐bis(4‐pyridyl)ethane), were prepared and structurally characterized by a single‐crystal X‐ray diffraction method. In compound 1 , each Cd(II) ion is six‐coordinate bonded to six nitrogen atoms from four 3‐bpd and two NCS? ligands. The 3‐bpd acts as a bridging ligand connecting the Cd(II) ion to generate a 2D layered metal‐organic framework (MOF) by using a rhomboidal‐grid as the basic building units with the 44 topology. In compound 2 , the Cd(II) ion is also six‐coordinate bonded to four nitrogen atoms of two 3‐bpd, two dpe and two oxygen atoms of two NO3? ligands. The 3‐bpd and dpe ligands both adopt bis‐monodentate coordination mode connecting the Cd(II) ions to generate a 2D layered MOF by using a rectangle‐grid as the basic building units with the 44 topology. In compound 3 , two crystallographically independent Cd(II) ions are both coordinated by four nitrogen atoms of dpe ligands in the basal plane and two nitrogen atom of NCS? in the axial sites. The dpe acts as a bridging ligand to connect the Cd(II) ions forming a 2D interpenetrating MOFs by using a square‐grid as the basic unit with the 44 topology. All of their 2D layered MOFs in compounds 1 ‐ 3 are then arranged in a parallel non‐interpenetrating ABAB—packing manner in 1 and 2 , and mutually interpenetrating manner in 3 , respectively, to extend their 3D supramolecular architectures with their 1D pores intercalated with solvent (ethanol in 1 or H2O in 3 ) or free 3‐bpd molecules in 2 and 3 , respectively. The photoluminescence measurements of 1 ‐ 3 reveal that the emission is tentatively assigned to originate from π‐π* transition for 1 and 2 and probably due to ligand‐center luminescence for compounds 3 , respectively.  相似文献   

14.
Two new salts, namely 2,6‐diamino‐4‐chloropyrimidinium 2‐carboxy‐3‐nitrobenzoate, C4H6ClN4+·C8H4NO6, (I), and 2,6‐diamino‐4‐chloropyrimidinium p‐toluenesulfonate monohydrate, C4H6ClN4+·C7H7O3S·H2O, (II), have been synthesized and characterized by single‐crystal X‐ray diffraction. In both crystal structures, the N atom in the 1‐position of the pyrimidine ring is protonated. In salt (I), the protonated N atom and the amino group of the pyrimidinium cation interact with the carboxylate group of the anion through N—H…O hydrogen bonds to form a heterosynthon with an R 22(8) ring motif. In hydrated salt (II), the presence of the water molecule prevents the formation of the familiar R 22(8) ring motif. Instead, an expanded ring [i.e. R 32(8)] is formed involving the sulfonate group, the pyrimidinium cation and the water molecule. Both salts form a supramolecular homosynthon [R 22(8) ring motif] through N—H…N hydrogen bonds. The molecular structures are further stabilized by π–π stacking, and C=O…π, C—H…O and C—H…Cl interactions.  相似文献   

15.
Reaction of a imidazole phenol ligand 4‐(imidazlo‐1‐yl)phenol (L) with 3d metal salts afforded four complexes, namely, [Ni(L)6] · (NO3)2 ( 1 ), [Cu(L)4(H2O)] · (NO3)2 · (H2O)5 ( 2 ), [Zn(L)4(H2O)] · (NO3)2 · (H2O) ( 3 ), and [Ag2(L)4] · SO4 ( 4 ). All complexes are composed of monomeric units with diverse coordination arrangements and corresponding anions. All the hydroxyl groups of monomeric cations are used as hydrogen‐bond donors to form O–H ··· O hydrogen bonds. However, the coordination habit of different metal ions produces various supramolecular structures. The NiII atom shows octahedral arrangement in 1 , featuring a 3D twofold inclined interpenetrated network through O–H ··· O hydrogen bond and π–π stacking interaction. The CuII atom of 2 displays square pyramidal environment. The O–H ··· O hydrogen bond from the [Cu(L)4(H2O)]2+ cation and lattice water molecule as well as π–π stacking produce one‐dimensional open channels. NO3 ions and lattice water molecules are located in the channels. 3 is a 3D supramolecular network, in which ZnII has a trigonal bipyramid arrangement. Two different rings intertwined with each other are observed. The AgI in 4 has linear and triangular coordination arrangements. The mononuclear units are assembled into a 1D chain by hydrogen bonding interaction from coordination units and SO42– anions.  相似文献   

16.
The reactions of anthraquinone‐2,6‐disulfonic acid disodium salt (Na2a‐2,6‐dad) with CuII, MnII, and ZnII with 1,10‐phenanthroline (phen) or 2,2′‐dipyridyl (bipy) under hydrothermal conditions formed two or three‐dimensional supramolecules of stoichiometries [Cu(a‐2,6‐dad)(phen)(H2O)3](H2O)4 ( 1 ), [Mn(a‐2,6‐dad)(bipy)2(H2O)](H2O)2 ( 2 ), and [Zn(a‐2,6‐dad)(bipy)2(H2O)](H2O)2 ( 3 ), which were synthesized and characterized. The arrangement around each metal atom is distorted octahedral. The ligands in all the compounds are engaged in intermolecular hydrogen bonding leading to the formation of hydrogen‐bonded networks, the compounds show novel π–π stacking interactions. Photoluminescence measurements indicate that the compound [Zn(a‐2,6‐dad)(bipy)2(H2O)](H2O)2 ( 3 ) shows strong blue luminescence in the solid state at room temperature.  相似文献   

17.
Carbon monoxide (CO) has recently been identified as a gaseous signaling molecule that exerts various salutary effects in mammalian pathophysiology. Photoactive metal carbonyl complexes (photoCORMs) are ideal exogenous candidates for more controllable and site‐specific CO delivery compared to gaseous CO. Along this line, our group has been engaged for the past few years in developing group‐7‐based photoCORMs towards the efficient eradication of various malignant cells. Moreover, several such complexes can be tracked within cancerous cells by virtue of their luminescence. The inherent luminecscent nature of some photoCORMs and the change in emission wavelength upon CO release also provide a covenient means to track the entry of the prodrug and, in some cases, both the entry and CO release from the prodrug. In continuation of the research circumscribing the development of trackable photoCORMs and also to graft such molecules covalently to conventional delivery vehicles, we report herein the synthesis and structures of three rhenium carbonyl complexes, namely, fac‐tricarbonyl[2‐(pyridin‐2‐yl)‐1,3‐benzothiazole‐κ2N ,N ′](4‐vinylpyridine‐κN )rhenium(I) trifluoromethanesulfonate, [Re(C7H7N)(C12H8N2S)(CO)3](CF3SO3), ( 1 ), fac‐tricarbonyl[2‐(quinolin‐2‐yl)‐1,3‐benzothiazole‐κ2N ,N ′](4‐vinylpyridine‐κN )rhenium(I) trifluoromethanesulfonate, [Re(C7H7N)(C16H10N2S)(CO)3](CF3SO3), ( 2 ), and fac‐tricarbonyl[1,10‐phenanthroline‐κ2N ,N ′](4‐vinylpyridine‐κN )rhenium(I) trifluoromethanesulfonate, [Re(C7H7N)(C12H8N2)(CO)3](CF3SO3), ( 3 ). In all three complexes, the ReI center resides in a distorted octahedral coordination environment. These complexes exhibit CO release upon exposure to low‐power UV light. The apparent CO release rates of the complexes have been measured to assess their comparative CO‐donating capacity. The three complexes are highly luminescent and this in turn provides a convenient way to track the entry of the prodrug molecules within biological targets.  相似文献   

18.
The blue copper complex [Cu2(H2O)2(phen)2(OH)2][Cu2(phen)2(OH)2(CO3)2] · 10 H2O, which was prepared by reaction of 1,10‐phenanthroline monohydrate, CuCl2 · 2 H2O and Na2CO3 in the presence of succinic acid in CH3OH/H2O at pH = 13.0, crystallized in the triclinic space group P1 (no. 2) with cell dimensions: a = 9.515(1) Å, b = 12.039(1) Å, c = 12.412(2) Å, α = 70.16(1)°, β = 85.45(1)°, γ = 81.85(1)°, V = 1323.2(2) Å3, Z = 1. The crystal structure consists of dinuclear [Cu2(H2O)2(phen)2(OH)2]2+ complex cations, dinuclear [Cu2(phen)2(OH)2(CO3)2]2– complex anions and hydrogen bonded H2O molecules. In both the centrosymmetric dinuclear cation and anion, the Cu atoms are coordinated by two N atoms of one phen ligand, three O atoms of two μ‐OH groups and respectively one H2O molecule or one CO32– anion to complete distorted [CuN2O3] square‐pyramids with the H2O molecule or the CO32– anion at the apical position (equatorial d(Cu–O) = 1.939–1.961 Å, d(Cu–N) = 2.026–2.051 Å and axial d(Cu–O) = 2.194, 2.252 Å). Two adjacent [CuN2O3] square pyramids are condensed via two μ‐OH groups. Through the interionic hydrogen bonds, the dinuclear cations and anions are linked into 1D chains with parallel phen ligands on both sides. Interdigitation of phen ligands of neighboring 1D chains generated 2D layers, between which the hydrogen bonded water molecules are sandwiched.  相似文献   

19.
The tris‐bidentate complex [Ni(C12H8N2)2(CO3)] was synthesized by the reaction of Na2CO3, 1,10‐phenanthroline (phen = C12H8N2) and NiSO4 · 6 H2O in the presence of succinic acid in a CH3OH–H2O solution. The compound crystallizes as heptahydrate. The crystal structure (monoclinic, P21/c (no. 14), a = 9.897(1), b = 26.384(2), c = 10.582(1) Å, β = 105.87(1)°, Z = 4, R = 0.0505, wR2 = 0.1029 for 3166 observed reflections (F ≥ 2σ(F ) out of 6100 unique reflections) consists of hydrogen bonded water molecules and [Ni(phen)2(CO3)] complex molecules. The Ni atoms are sixfold octahedrally coordinated by the four N atoms of two bidentate chelating phen ligands and by two O atoms of the bidentate chelating carbonate group with d(Ni–N) = 2.092–2.100 Å, d(Ni–O) = 2.051, 2.079 Å. The complex molecules are stacked into 2D corrugated layers parallel to (010) via two types of intermolecular π‐π stacking interactions. One occurs between two quinoline rings of neighboring phen ligands at the distance of 3.63 Å in [010] direction and the other results from 1D π‐π stacking interactions through partially covered phen rings at alternative distances of 3.26 Å and 3.33 Å in [001] direction. The water molecules are sandwiched between 2D layers.  相似文献   

20.
Five new complex compounds of the formula Ln(phen)2(NO3)3 were prepared. The X‐ray structural analyses indicate that they crystallize isostructurally in the monoclinic space group C2/c (no. 15) with cell dimensions for example for Pr(phen)2(NO3)3: a = 11.194(1) Å, b = 18.095(2) Å, c = 13.101(2) Å, β = 100.52(1)°, V = 2609.1(6) Å3, Z = 4. The crystal structures consist of [Ln(phen)2(NO3)3] complex molecules. The rare earth atoms are coordinated by four N atoms of two phen ligands and six O atoms of three nitrato groups to complete a distorted bicapped dodecahedron. The [Ln(phen)2(NO3)3] complex molecules are assembled via π‐π stacking interactions between the neighboring phen ligands to form 1D columnar chains, which are then arranged in the crystal structures according to pseudo 1D close‐packed patterns.  相似文献   

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