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1.
李宝龙  徐艳  刘琦  王化勤  徐正 《中国化学》2002,20(2):187-190
IntroductionCrystalengineeringofsupramoleculararchitecturessustainedbycoordinatecovalentbondsorhydrogenbondsrepresentsarapidlyexpandingfieldthatofferspo tentialfordevelopmentofnewclassesoffunctionalsolids .1,2 Thearchitecturesofcoordinationpolymerscanbe…  相似文献   

2.
Polyoxometalates (POMs)containingKegginmoi etieshavebeenreceivingextensiveattentioninrecentyearsowingtotheirgreatfundamentalandpracticalinter est .1Especiallytheunusualelectronicproperty (highnegativecharges) ,oneofthemostimportantpropertiesofPOMs ,haspoten…  相似文献   

3.
1 INTRODUCTIONAlthoughthebinuclearoxomolybdenum (V )compoundsofethylenedi aminetetraacetate (EDTA)chelateligandwerewidelystudiedduringlater 50s[1~ 4],thefirstsuchcrystalstructureofpotassiumsaltdidnotappearuntil1 967[5 ],andan otherstructureofsodiumsaltwasreportedi…  相似文献   

4.
胡茂林  林娟娟  缪谦  熊轶 《中国化学》2002,20(3):235-239
IntroductionThenitrilotriaceticacidisoneoftheimportantderivativesofglycine .Duringthelastdecade ,itstriva lentanion (NTA) ,asabridgingligand ,hasattractedwideattentionandbecomeoneofthesubjectofintensiveresearchforseveralreasons .1 6EachNTAhasthreecar boxylate…  相似文献   

5.
1INTRODUCTIONInrecentyears,aseriesoflanthanide aluminiumcomplexeswhichareactiveforpoly merizationofolfins〔1〕havebeenreported....  相似文献   

6.
IntroductionMolecularpolymerswithonedimensionalormulti dimensionalstructureassembledthroughhydrogenbondsisanimportantresearchcontentinthesupra molecularchemistryandcrystalengineering .1,2 Withthedevelop mentofnewtypefunctionalmaterialssuchasmolecularmagn…  相似文献   

7.
1 INTRODUCTIONCertaincoppercomplexeshavebeenshowntohaveunusualchemicalpropertiessuchasoxygentransfer,oxidativeadditionandhomogenouscatalytichydrogenation[1].Oxidativeadditionreactionsarekeystepsintheactivationofσbondsinagreatnumberofcatalyticprocess.Cop…  相似文献   

8.
IntroductionSincethepioneerworksofClearfieldandcoworkersinthe 196 0s ,1,2 layeredmetalphosphateshaveattractedmuchattentionduetotheirapplicationsonionex change ,intercalation ,heterogeneouscatalysisandsorp tion .3 7Amongthenumerouslamellarphases ,theproto typical…  相似文献   

9.
IntroductionThesupramolecularcomplexeformedbytheweakinteractions (electrostaticinteraction ,hydrogenbonds ,vanderWaalsforce ,short rangeexclusionforce ,etc .)ofmorethantwosortsofspeciesisanorganizingentitythatusuallypossessesspecialstructureandfunction .1Sup…  相似文献   

10.
IntroductionThesynthesisandsorptionpropertiesofopenframe worksolidssuchaszeolites1andmetalmolybdenumphos phate2 ,3withlargecavitiesprovokedenormousinterestbe causeoftheirpotentialapplicationincatalysis .One ,two andthree dimensionalsolidcompoundsconsistingo…  相似文献   

11.
The title compound, poly­[[[di­aqua(μ‐4,4′‐bipyridyl)­di­nickel(II)]‐bis(μ‐4,4′‐bipyridyl)‐di‐μ‐hexa­oxo­di­vana­date(2?)] 2.5‐hydrate], [Ni2­(V2O6)2­(C10H8N2)3­(H2O)2]·­2.5H2O, has been prepared hydro­thermally and characterized by elemental analyses, IR spectroscopy and single‐crystal X‐ray diffraction. The structure consists of [V2O6], [Ni­(4,4′‐bipy)4O2] and [Ni­(H2O)2­(4,4′‐bipy)2O2] polyhedra, and water of crystallization. The Ni atoms and one bipyridyl group lie on centres of symmetry.  相似文献   

12.
M(H2O)2(4,4′‐bipy)[C6H4(COO)2]·2H2O (M = Mn2+, Co2+) – Two Isotypic Coordination Polymers with Layered Structure Monoclinic single crystals of Mn(H2O)2(4,4′‐bipy)[C6H4(COO)2]·2H2O ( 1 ) and Co(H2O)2(4,4′‐bipy)[C6H4(COO)2]· 2H2O ( 2 ) have been prepared in aqueous solution at 80 °C. Space group P2/n (no. 13), Z = 2; 1 : a = 769.20(10), b = 1158.80(10), c = 1075.00(10) pm, β = 92.67(2)°, V = 0.9572(2) nm3; 2 : a = 761.18(9), b = 1135.69(9), c = 1080.89(9) pm, β = 92.276(7)°, V = 0.9337(2) nm3. M2+ (M = Mn, Co), which is situated on a twofold crystallographic axis, is coordinated in a moderately distorted octahedral fashion by two water molecules, two oxygen atoms of the phthalate anions and two nitrogen atoms of 4,4′‐biypyridine ( 1 : M–O 219.5(2), 220.1(2) pm, M–N 225.3(2), 227.2(2) pm; 2 : Co–O 212.7(2), 213.7(2) pm, Co–N 213.5(3), 214.9(3) pm). M2+ and [C6H4(COO)2)]2? build up chains, which are linked by 4,4′‐biyridine molecules to yield a two‐dimensional coordination polymer with layers parallel to (001).Thermogravimetric analysis in air of 1 indicated a loss of water of crystallization between 154 and 212 °C and in 2 between 169 and 222 °C.  相似文献   

13.
A new rarely reported ZnII mixed‐polypyridine coordination polymer with both rigid and flexible spacers, {[Zn(bpp)2(μ‐4,4′‐bipy)(H2O)2](ClO4)2 · H2O}n ( 1 ), has been synthesized and characterized by elemental analysis, IR‐, 1H NMR‐, 13C NMR spectroscopy and single‐crystal X‐ray diffraction. The thermal stability of compound 1 was studied by thermal gravimetric (TG) and differential thermal analyses (DTA). The single‐crystal X‐ray structure of 1 shows that the complex has been formed from a 1D polymer as a result of bridging by the 4,4′‐bipy ligands. Solution and solid‐state luminescent spectra of the compound 1 indicate intense fluorescent emissions at ca. 353.6 and 468.8 nm, respectively. Removal of the interstitial water guest molecules results in a loss of crystallinity, but exposure to water vapor reestablishes the original structure, thus constituting 1 as a third‐generation porous framework.  相似文献   

14.
The cadmium(II) 4‐sulfobenzoate complex with 4,4′‐bipyridine, {[Cd2(4,4′‐bipy)4(4‐sb)2(H2O)3] · 4H2O}n, has been synthesized and characterized by elemental analysis, IR, DTA‐TG, fluorescence analysis, powder X‐ray analysis, and single‐crystal X‐ray structural determination. Structural analysis showed that the complex contains two Cd atoms in an unsymmetrical unit. The Cd1 atom displays a seven‐coordinated geometry, which is a capped anti‐trigonal prismatic structure, whereas the Cd2 atom has an octahedral coordination. The 4,4′‐bipyridine ligands in the complex have three coordination behaviors, i.e., monodentate, dimeric linker, and polymeric bridge, which is the first example showing three coordinative functions for 4,4′‐bipyridine ligands in one complex. Moreover, three coordinative functions of 4,4′‐bipyridine ligands in this polymer lead to abundant weak interactions and novel fluorescent properties, which is benefit for design and preparation of functional materials in specific usage.  相似文献   

15.
The title compound, [HgCl2(C10H8N2)]n, features two‐dimensional [HgCl2(4,4′‐bipy)]n neutral networks (4,4′‐bipy is 4,4′‐bipyridine), based on an octahedral Hg atom coordinated by four μ2‐Cl atoms and two μ2‐4,4′‐bipy ligands in trans positions, yielding a HgCl4N2 octahedron. The structure has mmm symmetry about the Hg atoms, with most of the atoms on at least one mirror plane, but the unsubstituted C atoms of the 4,4′‐bipy rings are disordered across a mirror plane. Photoluminescent investigations reveal that the title compound displays a strong emission in the green region, which probably originates from a ligand‐to‐ligand charge‐transfer transition.  相似文献   

16.
A novel La( III )‐Cu( II ) heterometallic coordination polymer {[LaCu2(NTA)2(4,4′‐bpy)(H2O)3]NO3·5H2O]n, where H3NTA denotes nitrilotriacetic acid and 4,4′‐bpy denotes 4, 4‐bipyridine, was synthesized and characterized by IR spectrum, elemental analysis and X‐ray diffraction. The complex crystallizes in the triclinic space group Pi with cell parameters a = 1.33710(10) nm, b = 1,44530(10) nm, c =1.0949(2) nm, α = 71.905(7)°, β = 74.327(7)°, γ = 64.427(9)°, V = 1.7912(4) nm3and Z = 2. It consists of heterometallic units, in which each La( II ) ion is coordinated in a distorted monocapped square antiprism by three oxygen atoms from water molecules and six carboxyl oxygen atoms from five NTA3? ions, and each Cu( I ) ion is coordinated by one nitrogen atom from 4,4′‐bpy and one nitrogen atom, three oxygen atoms from NTA3?. In the title complex, La( I ) ions and Cu( II ) ions are connected by the heterometallic bridging of NTA3?, constructing a two‐dimensional network structure along the [110]. And it is extended into an infinite three‐dimensional network structure by the formation of homometallic bridging of Cu‐4, 4′‐bpy‐Cu, exhibiting a certain inclusion ability.  相似文献   

17.
The double‐chain coordination polymer, {[Zn(H2O)6][Zn(bbtc)H2O]·4H2O}n (bbtc = 3,3′, 4,4′‐benzophenonetetracarboxylate), features two kinds of zinc center. One is octahedrally coordinated by six aqua ligands and the other is coordinated by four carboxylate oxygen atoms, derived from three bbtc ligands, and a water molecule, forming a geometry intermediate between square‐pyramidal and trigonal bipyramidal. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

18.
A new coordination polymer (CP), namely poly[(μ‐4,4′‐bipyridine)(μ3‐3,4′‐oxydibenzoato)cobalt(II)], [Co(C14H8O5)(C10H8N2)]n or [Co(3,4′‐obb)(4,4′‐bipy)]n ( 1 ), was prepared by the self‐assembly of Co(NO3)2·6H2O with the rarely used 3,4′‐oxydibenzoic acid (3,4′‐obbH2) ligand and 4,4′‐bipyridine (4,4′‐bipy) under solvothermal conditions, and has been structurally characterized by elemental analysis, IR spectroscopy, single‐crystal X‐ray crystallography and powder X‐ray diffraction (PXRD). Single‐crystal X‐ray diffraction reveals that each CoII ion is six‐coordinated by four O atoms from three 3,4′‐obb2? ligands, of which two function as monodentate ligands and the other as a bidentate ligand, and by two N atoms from bridging 4,4′‐bipy ligands, thereby forming a distorted octahedral CoN2O4 coordination geometry. Adjacent crystallographically equivalent CoII ions are bridged by the O atoms of 3,4′‐obb2? ligands, affording an eight‐membered Co2O4C2 ring which is further extended into a two‐dimensional [Co(3,4′‐obb)]n sheet along the ab plane via 3,4′‐obb2? functioning as a bidentate bridging ligand. The planes are interlinked into a three‐dimensional [Co(3,4′‐obb)(4,4′‐bipy)]n network by 4,4′‐bipy ligands acting as pillars along the c axis. Magnetic investigations on CP 1 disclose an antiferromagnetic coupling within the dimeric Co2 unit and a metamagnetic behaviour at low temperature resulting from intermolecular π–π interactions between the parallel 4,4′‐bipy ligands.  相似文献   

19.
Attempts to crystal engineer metallosupramolecularcomplexes from Cu(phen)2+ building blocks and the prototypical,rod‐like, exo‐bidentate ligand 4,4′‐bipyridine (4,4′‐bipy) by layering techniques are described. Reactions of Cu(phen)2+ (phen = 1,10‐phenanthroline) with 4,4′‐bipy in the presence of NO3 counterions yielded two distinct, discrete, dinuclear, Ci symmetric, dumbbell‐typecomplexes, [{Cu(NO3)2(phen)}2(4,4′‐bipy)] ( 1 ) and [{Cu(NO3)(phen)(H2O)}2(4,4′‐bipy)](NO3)2 ( 2 ), depending upon the mixture of solvents used for crystallization. In compound 1 , a mono‐ and a bidentate nitrato group coordinate to Cu2+, whereas in 2 the monodentate nitrato groups are replaced by aqua ligands, which introduce additional hydrogen‐bond donor functionality to the molecule. The crystal structure of 1 was determined by single‐crystal X‐ray analysis at 296 and 110 K. Upon cooling, a disorder‐order transition occurs, with retention of the space group symmetry. The crystal structure of 2 at room temperature was reported previously [Z.‐X. Du, J.‐X. Li, Acta Cryst. 2007 , E63, m2282]. We have redetermined the crystal structure of 2 at 100 K. A phase transition is not observed for 2 , but the low temperature single‐crystal structure determination is of significantly higher precision than the room temperature study. Both 1 and 2 are obtained phase‐pure, as proven by powder X‐ray diffraction of the bulk materials. Crystals of [Cu(phen)(CF3SO3)2(4,4′‐bipy) · 0.5H2O]n ( 3 ), a one‐dimensional coordination polymer, were obtained from [Cu(CF3SO3)2(phen)(H2O)2] and 4,4′‐bipy. In 3 , Cu(phen)2+ corner units are joined by 4,4′‐bipy via the two vacant cis sites to form polymeric zig‐zag chains, which are tightly packed in the crystal. Compounds 1 – 3 were further studied by infrared spectroscopy.  相似文献   

20.
The polymeric title complex, {[Mn(C4H4O4)(C10H8N2)(H2O)]·0.5C10H8N2}n, possesses a three‐dimensional open‐framework structure, with the solvate 4,4′‐bi­pyridine (bipy) mol­ecules, which lie around centers of inversion, clathrated in the channels of the framework. The MnII center is surrounded by three succinate (succ) ligands, one water mol­ecule and two bipy ligands, and displays a slightly distorted octahedral coordination environment, with cis angles ranging from 84.14 (12) to 96.56 (11)°. Each succ dianion coordinates to three MnII atoms, thus acting as a bridging tridentate ligand; in turn, the MnII atoms are bridged by three succ ligands, thus forming a two‐dimensional Mn–succ sheet pillared by the bridging bipy ligands. Two hydrogen‐bonding interactions, involving the water mol­ecules and the carboxy O atoms of the succ ligands, are present in the crystal structure.  相似文献   

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