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1.
Glen B. Deacon Prof. Dr. Peter C. Junk Prof. Dr. Graeme J. Moxey Karin Ruhlandt‐Senge Prof. Dr. Courtney St. Prix Dr. Maria F. Zuniga Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(22):5503-5519
A new family in town! Treatment of a rare‐earth metal (Ln) and either a potential divalent rare‐earth metal (Ln′) or an alkaline earth metal (Ae) with 2,6‐diphenylphenol (HOdpp) at elevated temperatures (200–250 °C) afforded heterobimetallic aryloxo complexes (see figure). Both a charge‐separated species, [(Ln′/Ae)2(Odpp)3][Ln(Odpp)4], and a neutral species, [AeEu(Odpp)4], were obtained and crystallographically characterised.
2.
Redox transmetallation ligand exchange reactions involving a rare earth metal, 2,4,6‐trimethylphenol (HOmes), and a diarylmercurial afford rare earth aryloxo complexes, which are structurally characterized. Both the lanthanoid contraction and the identity of the reaction solvent are found to influence the outcome of the reactions. Using THF in the reaction affords a dinuclear species [Ln2(Omes)6(thf)4]?2THF (Ln=La 1 , Nd 2 ) for the lighter rare earth metals, while a mononuclear species [Ln(Omes)3(thf)3] (Ln=Sm 3 , Tb 5 , Er 6 , Yb 7 , Y 8 ) is obtained for the heavier rare earth elements. Surprisingly, there is no change in metal coordination number between the two structural motifs. A divalent trinuclear linear complex [Eu3(Omes)6(thf)6] 4 is obtained for Eu, and features solely bridging aryloxide ligands. Using DME as the reaction solvent affords [La(Omes)3(dme)2] 9 from the reaction mixture, and [Ln2(Omes)6(dme)2]?PhMe (La 10 , Nd 11 ) and [Y(Omes)3(dme)2] 14 following crystallization of the crude product from toluene. The dinuclear species [Eu2(Omes)4(dme)4] 12 contains two unidentate and two chelating DME ligands, and contrasts the linear structure of 4 . Treatment of HOmes and HgPh2 with Yb metal in DME affords the mixed valent YbII/III complex [Yb2(Omes)5(dme)2] 13 , which is stabilized by an intramolecular π‐Ph–Yb interaction, and is a rare example of a mixed valent rare earth aryloxide. Treatment of Er metal with HOmes at elevated temperature (solvent free) affords the homoleptic [Er4(Omes)12] 15 , which consists of a tetranuclear array of Er atoms arranged in a ‘herringbone’ fashion; the structure is stabilized by intramolecular π‐Ph–Er interactions. Reaction of La metal with HOmes under similar conditions yields toluene insoluble “La(Omes)3”, which affords 1 following extraction with THF. 相似文献
3.
Zuniga MF Deacon GB Ruhlandt-Senge K 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(7):1921-1928
The preparation of heterobimetallic complexes consisting of alkali and heavy alkaline earth metals remains a challenge due to limited available synthetic strategies. Here we present a new class of group 1, Ba compounds of the type [M(n){Ba(Odpp)(2+n)}] (M=Na(n=1) (1), K(n=1) (2), Cs(n=1) (3), Li(n=2) (4); HOdpp=2,6-diphenylphenol) and the Lewis base adducts [Li(2)(thf)(2){Ba(Odpp)(4)}]PhMe (5) and [K{Ba(Odpp)(3)(diglyme)}] (6) (diglyme=[bis(2-methoxy)ethyl ether]) as the first representatives of heterobimetallic group 1, Ba species of low nuclearity. The compounds display a significant degree of metal-arene interaction, believed to be a key factor in stabilizing these highly reactive species. Obtained by solid-state direct metalation, the target compounds are available without further work-up. 相似文献
4.
Klaus Müller‐Buschbaum 《无机化学与普通化学杂志》2004,630(6):895-899
Low‐Temperature Oxidation in Liquid Ammonia: [Eu2(Ind)4(NH3)6], the First Indolate of a Rare Earth Element Intensively yellow to orange coloured, transparent crystals of [Eu2(Ind)4(NH3)6] were obtained by low‐temperature oxidation of europium metal with indole (C8H6NH) in liquid ammonia at —50 °C and subsequent melting of the reaction mixture in excess indole at 120 °C. [Eu2(Ind)4(NH3)6] has a dimeric structure and contains divalent Eu. The coordination sphere around the europium atoms consists of five N atoms of two cisoid indolate anions and three NH3 molecules as well as an η5‐coordinating π‐system of another indolate ligand, bridging to the next Eu atom with an sp2‐orbital. 相似文献
5.
Yasuchika Hasegawa Ryo Hieda Tetsuya Nakagawa Tsuyoshi Kawai 《Helvetica chimica acta》2009,92(11):2238-2248
Novel EuIII complexes with bidentate phosphine oxide ligands containing a bipyridine framework, i.e., [3,3′‐bis(diphenylphosphoryl)‐2,2′‐bipyridine]tris(hexafluoroacetylacetonato)europium(III) ([Eu(hfa)3(BIPYPO)]) and [3,3′‐bis(diphenylphosphoryl)‐6,6′‐dimethyl‐2,2′‐bipyridine]tris(hexafluoroacetylacetonato)europium(III) ([Eu(hfa)3(Me‐BIPYPO)]), were synthesized for lanthanide‐based sensor materials having high emission quantum yields and effective chemosensing properties. The emission quantum yields of [Eu(hfa)3(BIPYPO)] and [Eu(hfa)3(Me‐BIPYPO)] were 71 and 73%, respectively. Metal‐ion sensing properties of the EuIII complexes were also studied by measuring the emission spectra of EuIII complexes in the presence of ZnII or CuII ions. The metal‐ion sensing and the photophysical properties of luminescent EuIII complexes with a bidentate phosphine oxide containing 2,2′‐bipyridine framework are demonstrated for the first time. 相似文献
6.
Multifunctional Lanthanide‐Based Metal–Organic Frameworks with a Polyheterotopic Ligand: Doped with Ytterbium(III) for Luminescence Enhancement and Selective Dye Adsorption 下载免费PDF全文
《化学:亚洲杂志》2018,13(16):2126-2134
The chemistry of metal–organic frameworks has been progressing fast with its exciting potential in multifunctional applications. A series of three‐dimensional lanthanide‐based metal–organic frameworks, {[Ln(HTPO)(NO3)(H2O)]⋅x(CH3CN)⋅y(H2O)}n (Ln=Eu ( 1 ), Tb ( 2 ), Gd ( 3 ), Sm ( 4 ), Dy ( 5 ), Nd ( 6 )), {[Eu(TPO)(HCOO)0.5]⋅(H3O)0.5}n ( 7 ), {[Eu(TPO)(DMF)]⋅(solv)x}n ( 8 ; DMF= N,N‐dimethylformamide), and {[Eu(TPO)(DMA)]⋅(solv)x}n ( 9 ; DMA=dimethylacetamide) were synthesized with semirigid C3‐symmetric ligand tris(4‐carboxylphenyl)phosphine oxide (H3TPO). In these frameworks, the H3TPO ligand exists in a totally different configuration. Framework 1 exhibits good breathing properties for absorbing more guest molecules through a solvent‐induced single‐crystal‐to‐single‐crystal (SC–SC) transformation involving a configuration transformation of the organic linker in the framework. The ytterbium ion was doped into 1 to improve the luminescent performance (lifetime and quantum yield) of the red europium emission. Among a series of Eu1−xYbxTPO samples, Eu0.88Yb0.12TPO showed enhanced luminescence intensity (≈5.1 times that of the pure europium system), and the lifetime increased from 1073.08 to 1236.57 μs. Moreover, the porosity of these frameworks allows them to efficiently adsorb dye molecules with high selectivity and efficiency. 相似文献
7.
Gaël Zucchi Dr. Olivier Maury Dr. Pierre Thuéry Dr. Frédéric Gumy Jean‐Claude G. Bünzli Prof. Dr. Michel Ephritikhine Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(38):9686-9696
Treatment of Ln(NO3)3?nH2O with 1 or 2 equiv 2,2′‐bipyrimidine (BPM) in dry THF readily afforded the monometallic complexes [Ln(NO3)3(bpm)2] (Ln=Eu, Gd, Dy, Tm) or [Ln(NO3)3(bpm)2]?THF (Ln=Eu, Tb, Er, Yb) after recrystallization from MeOH or THF, respectively. Reactions with nitrate salts of the larger lanthanide ions (Ln=Ce, Nd, Sm) yielded one of two distinct monometallic complexes, depending on the recrystallization solvent: [Ln(NO3)3(bpm)2]?THF (Ln=Nd, Sm) from THF, or [Ln(NO3)3(bpm)(MeOH)2]?MeOH (Ln=Ce, Nd, Sm) from MeOH. Treatment of UO2(NO3)2?6H2O with 1 equiv BPM in THF afforded the monoadduct [UO2(NO3)2(bpm)] after recrystallization from MeOH. The complexes were characterized by their crystal structure. Solid‐state luminescence measurements on these monometallic complexes showed that BPM is an efficient sensitizer of the luminescence of both the lanthanide and the uranyl ions emitting visible light, as well as of the YbIII ion emitting in the near‐IR. For Tb, Dy, Eu, and Yb complexes, energy transfer was quite efficient, resulting in quantum yields of 80.0, 5.1, 70.0, and 0.8 %, respectively. All these complexes in the solid state were stable in air. 相似文献
8.
Ayjamal Ablet Shu‐Mu Li Wei Cao Dr. Xiang‐Jun Zheng Prof. Wing‐Tak Wong Prof. Lin‐Pei Jin 《化学:亚洲杂志》2013,8(1):95-100
Four new three‐dimensional isostructural lanthanide–cadmium metal–organic frameworks (Ln–Cd MOFs), [LnCd2(imdc)2(Ac)(H2O)2]?H2O (Ln=Pr ( 1 ), Eu ( 2 ), Gd ( 3 ), and Tb ( 4 ); H3imdc=4,5‐imidazoledicarboxylic acid; Ac=acetate), have been synthesized under hydrothermal conditions and characterized by IR, elemental analyses, inductively coupled plasma (ICP) analysis, and X‐ray diffraction. Single‐crystal X‐ray diffraction shows that two LnIII ions are surrounded by four CdII ions to form a heteronuclear building block. The blocks are further linked to form 3D Ln–Cd MOFs by the bridging imdc3? ligand. Furthermore, the left‐ and right‐handed helices array alternatively in the lattice. Eu–Cd and Tb–Cd MOFs can emit characteristic red light with the EuIII ion and green light with the TbIII ion, respectively, while both Gd–Cd and Pr–Cd MOFs generate blue emission when they are excited. Different concentrations of Eu3+ and Tb3+ ions were co‐doped into Gd–Cd/Pr–Cd MOFs, and tunable luminescence from yellow to white was achieved. White‐light emission was obtained successfully by adjusting the excitation wavelength or the co‐doping ratio of the co‐doped Gd–Cd and Pr–Cd MOFs. These results show that the relative emission intensity of white light for Gd–Cd:Eu3+,Tb3+ MOFs is stronger than that of Pr–Cd:Eu3+,Tb3+ MOFs, which implies that the Gd complex is a better matrix than the Pr complex to obtain white‐light emission materials. 相似文献
9.
Keggin‐Type Polyoxometalate‐Based Metal–Organic Networks for Photocatalytic Dye Degradation 下载免费PDF全文
Hong‐Fang Hao Wen‐Zhe Zhou Prof. Hong‐Ying Zang Dr. Hua‐Qiao Tan Dr. Yan‐Fei Qi Dr. Yong‐Hui Wang Prof. Yang‐Guang Li 《化学:亚洲杂志》2015,10(8):1676-1683
The reaction of Keggin‐type polyoxometalate (POM) units, transition‐metal (TM) ions, and a rigid bis(imidazole) ligand (1,4‐bis(1‐imidazolyl)benzene (bimb)) in a hydrothermal environment led to the isolation of four new POM‐based metal–organic networks, [H2L][CuL][SiW12O40]?2 H2O ( 1 ), [H2L]2[Co(H2O)3L][SiW11CoO39]?6 H2O ( 2 ), KH[CuL]2[SiW11CoO39(H2O)]?2 H2O ( 3 ), and [CuL]4[GeW12O40]?H2O ( 4 ; L=bimb). All four compounds were characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, powder X‐ray diffraction, and single‐crystal X‐ray diffraction. Compounds 1 and 3 are new 3D networks with 1D channels. Compounds 2 and 4 contain 2D networks, which further stack into 3D supramolecular networks. The contributions of pH value, the negative charge of the POM, and the TM coordination modes to the construction of 3D networks were elucidated by comparing the synthetic conditions and structures of compounds 1 – 4 . The photocatalytic properties of compounds 1 – 4 were investigated using methylene blue (MB) degradation under UV light. All compounds showed good catalytic activity and structural stability. The possible catalytic mechanism was discussed on the basis of active‐species trapping experiments. The different photocatalytic activities of compounds 1 – 4 were explained by comparison of the band gaps of different POM species and different packing modes of POM units in these hybrid compounds. 相似文献
10.
Highly Selective Detection of 2,4,6‐Trinitrophenol and Cu2+ Ions Based on a Fluorescent Cadmium–Pamoate Metal–Organic Framework 下载免费PDF全文
Dr. Junwei Ye Limei Zhao Raji Feyisa Bogale Yuan Gao Xiaoxiao Wang Xiaomin Qian Song Guo Prof. Jianzhang Zhao Prof. Guiling Ning 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(5):2029-2037
A luminescent cadmium–pamoate metal–organic framework, [Cd2(PAM)2(dpe)2(H2O)2]?0.5(dpe) ( 1 ), has been synthesized under hydrothermal conditions by using π‐electron‐rich ligands 4,4′‐methylenebis(3‐hydroxy‐2‐naphthalenecarboxylic acid) (H2PAM) and 1,2‐di(4‐pyridyl)ethylene (dpe). Its structure is composed of both mononuclear and dinuclear CdII building units, which are linked by the PAM and dpe ligands, resulting in a (4,8)‐connected 3D framework. The π‐conjugated dpe guests are located in a 1D channel of 1 . The strong emission of 1 could be quenched efficiently by trace amounts of 2,4,6‐trinitrophenol (TNP), even in the presence of other competing analogues such as 4‐nitrophenol, 2,6‐dinitrotoluene, 2,4‐dinitrotoluene, nitrobenzene, 1,3‐dinitrobenzene, hydroquinone, dimethylbenzene, and bromobenzene. The high sensitivity and selectivity of the fluorescence response of 1 to TNP shows that this framework could be used as an excellent sensor for identifying and quantifying TNP. In the same manner, 1 also exhibits superior selectivity and sensitivity towards Cu2+ compared with other metal ions such as Zn2+, Mn2+, Mg2+, K+, Na+, Ni2+, Co2+, and Ca2+. This is the first MOF that can serve as a dual functional fluorescent sensor for selectively detecting trace amounts of TNP and Cu2+. 相似文献
11.
Three new isostructural 3D lanthanide metal–organic frameworks (Ln‐MOFs), {H[LnL(H2O)]?2 H2O}n ( 1‐Ln ) (Ln=Eu3+, Gd3+ and Tb3+), based on infinite lanthanide‐carboxylate chains were constructed by employing an ether‐separated 5,5′‐oxydiisophthalic acid (H4L) ligand under solvothermal reaction. 1‐Eu and 1‐Tb exhibit strong red and green emission, respectively, through the antenna effect, as demonstrated through a combination of calculation and experimental results. Moreover, a series of dichromatic doped 1‐EuxTby MOFs were fabricated by introducing different concentrations of Eu3+ and Tb3+ ions, and they display an unusual variation of luminescent colors from green, yellow, orange to red. 1‐Eu with channels decorated by ether O atoms and the open metal sites displays good performance for CO2 capture and conversion between CO2 and epoxides into cyclic carbonates. 相似文献
12.
Homo‐ and Heteronuclear Compounds with a Symmetrical Bis‐hydrazone Ligand: Synthesis,Structural Studies,and Luminescent Properties 下载免费PDF全文
Dr. Sabina Rodríguez‐Hermida Dr. Ana B. Lago Prof. Rosa Carballo Dr. Oscar Fabelo Prof. Ezequiel M. Vázquez‐López 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(17):6605-6616
Nine new coordination compounds have been synthesized by the reaction of salts of bivalent metal ions (a=ZnII, b=CuII, c=NiII, d=CoII) with the bis(benzoylhydrazone) derivative of 4,6‐diacetylresorcinol (H4L). Three kinds of complexes have been obtained: homodinuclear compounds [M2(H2L)2]?nH2O ( 1 a , 1 b , 1 c , and 1 d ), homotetranuclear compounds [M4(L)2]?n(solv) ( 2 a and 2 c ), and heterotetranuclear compounds [Zn2M2(L)2]?n(solv) ( 2 ab , 2 ac , and 2 ad ). The structures of the free ligand H4L?2 DMSO and its complexes [Zn2(H2L)2(DMSO)2] ( 1 a* ), [Zn4(L)2(DMSO)6] ( 2 a* ), and [Zn0.45Cu3.55(L)2(DMSO)6]?2 DMSO ( 2 ab* ) were elucidated by single‐crystal X‐ray diffraction. The ligand shows luminescence properties and its fluorimetric behavior towards MII metals (M=Zn, Cu, Ni and Co) has been studied. Furthermore, the solid‐state luminescence properties of the ligand and compounds have been determined at room temperature. 1H NMR spectroscopic monitoring of the reaction of H4L with ZnII showed the deprotonation sequence of the OH/NH groups upon metal coordination. Heteronuclear reactions have also been monitored by using ESI‐MS and spectrofluorimetric techniques. 相似文献
13.
Yuichi Hirai Dr. Takayuki Nakanishi Dr. Yuichi Kitagawa Dr. Koji Fushimi Dr. Tomohiro Seki Prof. Dr. Hajime Ito Prof. Dr. Yasuchika Hasegawa 《Angewandte Chemie (International ed. in English)》2016,55(39):12059-12062
Novel EuIII coordination polymers [Eu(hfa)3(dpt)]n (dpt: 2,5‐bis(diphenylphosphoryl)thiophene) and [Eu(hfa)3(dpedot)]n (dpedot: 2,5‐bis(diphenylphosphoryl)ethylenedioxythiophene) with hydrogen‐bonded zipper structures are reported. The coordination polymers are composed of EuIII ions, hexafluoroacetylacetonato ligands, and thiophene‐based phosphine oxide bridges. The zig‐zag orientation of single polymer chains induced the formation of densely packed coordination structures with multiple intermolecular interactions, resulting in thermal stability above 300 °C. They exhibit a high intrinsic emission quantum yield (ca. 80 %) due to their asymmetrical and low‐vibrational coordination structures around EuIII ions. Furthermore, the characteristic alternative orientation of substituents also contributes to the dramatically high ligand‐to‐metal energy transfer efficiencies of up to 80 % in the solid state. 相似文献
14.
Young Eun Cheon Myunghyun Paik Suh Prof. 《Angewandte Chemie (International ed. in English)》2009,48(16):2899-2903
Quick on the uptake : Palladium nanoparticles were fabricated simply by immersing {[Zn3(ntb)2(EtOH)2]?4 EtOH}n ( 1 ) in an MeCN solution of Pd(NO3)2 at room temperature, without any extra reducing agent. 3 wt % PdNPs@[ 1 ]0.54+(NO3?)0.54 significantly increase H2 uptake capacities, both at 77 K and 1 bar and at 298 K and high pressures (see picture, red curve) compared to [Zn3(ntb)2]n (black). ntb=4,4′,4′′‐nitrilotrisbenzoate.
15.
Shu‐Li Yao Xue‐Mei Tian Le‐Qian Li Sui‐Jun Liu Teng‐Fei Zheng Yong‐Qiang Chen Da‐Shuai Zhang Jing‐Lin Chen He‐Rui Wen Tong‐Liang Hu 《化学:亚洲杂志》2019,14(20):3648-3654
A new metal‐organic framework (MOF) {[Cd2(bbib)2(ndc)2]?2DMF}n ( JXUST‐1 ) (bbib=1,3‐bis(benzimidazolyl)benzene, H2ndc=1,4‐naphthalenedicarboxylic acid, DMF=N,N‐dimethylformamide) has been solvothermally synthesized and characterized by single‐crystal X‐ray diffraction, PXRD, TGA, IR and elemental analysis. JXUST‐1 exhibits a three‐dimensional 6‐connected pcu topology with a Schläfli symbol {412.63} constructed by [Cd2(CO2)3] secondary building units. Fluorescence studies show that this MOF can sensitively and selectively recognize Al3+ via a fluorescence enhancement effect, and the detection limit is 0.048 ppm. Furthermore, JXUST‐1 displays relatively good thermal and chemical stabilities as well as reusability. All these results suggest JXUST‐1 to be a highly selective and recyclable luminescent sensing material for the detection of Al3+. 相似文献
16.
A series of novel heterobimetallic group 1/strontium and group 1/calcium aryloxo complexes having the composition [MAe(Odpp)3] [Ae=Sr and M=Na (1), K (2, 3), Cs (4); Ae=Ca and M=Na (5), K (6), Cs (7)] or [M2Ae(Odpp)4] [M=Li and Ae=Sr (9), Ca (10)] have been prepared using 2,6-diphenylphenol (HOdpp) as the ligand. Through the use of solid-state direct metalation, these compounds were obtained either directly from the reaction vessel or after workup in toluene. The Lewis base adduct [KCa(Odpp)3(thf)] (8) was obtained by treatment of [KCa(Odpp)3] (6) with tetrahydrofuran (thf). All of the compounds displayed extensive metal-pi-arene interactions, which provide significant stabilization in these reactive species. The thermal stabilities and volatilities of representative heterobimetallic strontium and calcium complexes were investigated using thermogravimetric analysis. 相似文献
17.
Manfredo Hrner Gelson Manzoni de Oliveira Mariana Boneberger Behm Herton Fenner 《无机化学与普通化学杂志》2006,632(4):615-618
A solution of deprotonated 1,3‐bis(4‐bromophenyl)triazene reacts with Hg(CH3COO)2 in methanol / tetrahydrofurane to give yellow crystalline needles of {HgII[NNN(PhBr)2]2}n, a triazenide complex polymer of HgII with metal‐η2,η2‐arene π‐interactions, performed by coordinated single triazenide chains. The crystal structure of the new polymeric complex of HgII belongs to the monoclinic space group P21/n. The lattice of [HgII(BrPhNNNPhBr)2]n can be viewed as a one‐dimensional assembling of planar tectons [HgII(BrPhNNNPhBr)2] linked through metalocene alike HgII‐η2,η2‐arene π‐interactions along the crystallographic b axis. 相似文献
18.
A new triazine‐cored tricarboxylic acid, N,N′,N“‐1,3,5‐triazine‐2,4,6‐triyltris(cis‐4‐aminocyclohexane‐carboxylic acid) (H3L), has been prepared by replacing the chlorine atoms of cyanuric chloride with cis‐4‐aminocyclohexane‐carboxylic acid, which has been used for the construction of a series of triazine‐cored lanthanide‐based metal–organic frameworks (MOFs). All these MOFs were structurally authenticated, revealing that they are isostructural and exist as two‐dimensional (2D) coordination networks with the general formula [Ln(L)(H2O)2]?5.5 H2O (Ln= 1?Gd , 2?Tb , 3?Eu ). A unique one‐dimensional water chain, composed of primary tetrameric cyclic rings and dodecameric cyclic rings, has been found entrapped in the lattice. Moreover, all these compounds display bright characteristic photoluminescence. Particularly, for 1 , apart from the strong blue emission peak (Φf=20.6 %) corresponding to the intraligand transition under near‐UV excitation, the characteristic emissions of Gd3+ cation (Φf=5.0 %) were unexpectedly observed upon excitation at 273 nm. 相似文献
19.
Solvent‐Mediated Transformation from Achiral to Chiral Nickel(II) Metal–Organic Frameworks and Reassembly in Solution 下载免费PDF全文
Prof. Xiaoju Li Zhenjiang Yu Prof. Xinxiong Li Xiaofang Guo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(46):16593-16600
Reactions of 5‐nitroisophthalic acid (NO2‐H2ip), 1,4‐bis(imidazol‐1′‐yl)butane (bimb), and Ni(NO3)2 ? 6 H2O gave rise to four metal–organic frameworks (MOFs), [Ni2(NO2‐ip)2(bimb)1.5]n ( 1 ), [Ni4(NO2‐ip)3(bimb)2(OH)2(H2O)]n ? (CH3CH2OH)0.5 n ( 2 ), [Ni(NO2‐ip)(bimb)1.5(H2O)]n ? (H2O)n ? (CH3CH2OH)0.5 n ( 3 ), and [Ni(NO2‐ip) (bimb)(μ‐H2O)]n ? (H2O)n ( 4 ). The metal/ligand ratio, pH value, and solvent exerted a subtle but crucial influence on the formation of complexes 1 – 4 , which possess different visual color and crystal structures. Complex 1 exhibits a twofold interpenetrating 3D pillared bilayer framework composed of binuclear and mononuclear NiII units, whereas complex 2 is a 3D chiral network that consists of asymmetric tetranuclear NiII units. Complexes 3 and 4 are 3D layer‐pillared frameworks that consist of mononuclear NiII ions and a 3D six‐connected network of μ‐water‐bridged dinuclear NiII units, respectively. Interestingly, achiral 4 can be transformed into chiral 2 by using a solvent‐mediated single‐crystal‐to‐single‐crystal process without any chiral auxiliary. Magnetic analyses of 2 and 4 show the occurrence of antiferromagnetic interactions. Complex 3 is difficult to obtain directly as a single solid phase, but it can be homogeneously formed by solvent‐mediated transformations from 1 , 2 , and 4 . 相似文献
20.
Xia Li Ying‐Quan Zou Bo Zheng Huai‐Ming Hu 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(5):m197-m199
The title compound, [Eu(C9H9O4)3]n or [Eu(2,3‐DMOBA)3]n, where 2,3‐DMOBA is 2,3‐dimethoxybenzoate, is an infinite one‐dimensional non‐centrosymmetric coordination polymer. The unique EuIII atom is bridged by six carboxylate ligands; it is ennea‐coordinated and has a distorted tricapped trigonal prism geometry. The Eu—O distances are in the range 2.315 (3)–2.959 (5) Å. 相似文献