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1.
Jian Lü Dr. Wen‐Hua Bi Dr. Fu‐Xian Xiao Dr. Stuart R. Batten Dr. Rong Cao Dr. 《化学:亚洲杂志》2008,3(3):542-547
Three lanthanide coordination polymers constructed from infinite rod‐shaped secondary building units (SBUs), [Nd2(H2O)2(cis‐chdc)2(trans‐chdc)]?2H2O ( 1 ), Nd2(H2O)4(trans‐chdc)3 ( 2 ), and [Sm2(H2O)2(cis‐chdc)(trans‐chdc)2]?4H2O ( 3 ) (chdcH2=1,4‐cyclohexanedicarboxylic acid), were hydrothermally synthesized and structurally characterized. The structures of 1 – 3 are modulated by different ratios of the cis and trans configurations of chdc2? ligands, which was achieved by temperature control in the hydrothermal reactions. Crystal‐structure analysis revealed that 1 is a four‐connected pcu‐type rod packing network built from cross‐linking of rod‐shaped neodymium–oxygen SBUs by cis‐ and trans‐chdc2? ligands in a 2:1 ratio, 2 displays a complicated six‐connected hex‐type rod packing structure built by connection of rod‐shaped neodymium–oxygen SBUs and trans‐chdc2? ligands, and 3 features an unprecedented five‐connected rod packing pattern constructed from rod‐shaped samarium–oxygen SBUs and cis‐ and trans‐chdc2? ligands in a 1:2 ratio. 相似文献
2.
Anne‐Christine Chamayou Chaitali Biswas Ashutosh Ghosh Christoph Janiak 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(8):m311-m313
The crystal structure of the title compound, [Cu(C6H4NO2)(C2H3O2)(C3H4N2)(H2O)]·0.87H2O, has a square‐pyramidal‐coordinated CuII centre (the imidazole is trans to the picolinate N atom, the acetate is trans to the picolinate –CO2 group and the aqua ligand is in a Jahn–Teller‐elongated apical position) and has two symmetry‐independent molecules in the unit cell (Z′ = 2), which are connected through complementary imidazole–picolinate N—H...O hydrogen bonding. The two partially occupied solvent water molecules are each disordered over two positions. The disordered solvent water molecules, together with pseudosymmetry elements, support the notion that a crystal structure with multiple identical chemical formula units in the structural asymmetric unit (Z′ > 1) can represent a crystal `on the way', that is, a kinetic intermediate form which has not yet reached its thermodynamic minimum. Neighbouring molecules form π–π stacks between their imidazole and picolinate N‐heterocycles, with centroid–centroid distances in the range 3.582 (2)–3.764 (2) Å. 相似文献
3.
In‐Hyeok Park Prof. Dr. Shim Sung Lee Prof. Dr. Jagadese J. Vittal 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(8):2695-2702
Solvothermal reaction of Zn(NO3)2 ? 4 H2O, 1,4‐bis[2‐(4‐pyridyl)ethenyl]benzene (bpeb) and 4,4′‐oxybisbenzoic acid (H2obc) in the presence of dimethylacetamide (DMA) as one of the solvents yielded a threefold interpenetrated pillared‐layer porous coordination polymer with pcu topology, [Zn2(bpeb)(obc)2] ? 5 H2O ( 1 ), which comprised an unusual isomer of the well‐known paddle‐wheel building block and the trans–trans–trans isomer of the bpeb pillar ligand. When dimethylformamide (DMF) was used instead of DMA, a supramolecular isomer [Zn2(bpeb)(obc)2] ? 2 DMF ? H2O ( 2 ), with the trans–cis–trans isomer of the bpeb ligand with a slightly different variation of the paddle‐wheel repeating unit, was isolated. In MeOH, single crystals of 2 were transformed by solvent exchange in a single‐crystal‐to‐single‐crystal (SCSC) manner to yield [Zn2(bpeb)(obc)2] ? 2 H2O ( 3 ), which is a polymorph of 1 . SCSC conversion of 3 to 2 was achieved by soaking 3 in DMF. Compounds 1 and 2 as well as 2 and 3 are supramolecular isomers. 相似文献
4.
Soichiro Nakatsuka Yusuke Watanabe Yoshinobu Kamakura Satoshi Horike Daisuke Tanaka Takuji Hatakeyama 《Angewandte Chemie (International ed. in English)》2020,59(4):1435-1439
A triphosphaazatriangulene (H3L) was synthesized through an intramolecular triple phospha‐Friedel–Crafts reaction. The H3L triangulene contains three phosphinate groups and an extended π‐conjugated framework, which enables the stimuli‐responsive reversible transformation of [Cu(HL)(DMSO)?(MeOH)]n, a 3D‐MOF that exhibits reversible sorption characteristics, into (H3L?0.5 [Cu2(OH)4?6 H2O] ?4 H2O), a 1D‐columnar assembled proton‐conducting material. The hydrophilic nature of the latter resulted in a proton conductivity of 5.5×10?3 S cm?1 at 95 % relative humidity and 60 °C. 相似文献
5.
Silvia Cruz Jorge Trilleras Justo Cobo John N. Low Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(12):o637-o642
3‐tert‐Butyl‐7‐(4‐chlorobenzyl)‐4′,4′‐dimethyl‐1‐phenyl‐4,5,6,7‐tetrahydro‐1H‐pyrazolo[3,4‐b]pyridine‐5‐spiro‐1′‐cyclohexane‐2′,6′‐dione ethanol hemisolvate, C30H34ClN3O2·0.5C2H6O, (I), its 7‐(4‐bromobenzyl)‐ analogue, C30H34BrN3O2·0.5C2H6O, (II), and its 7‐(4‐methylbenzyl)‐ analogue, C31H37N3O2·0.5C2H6O, (III), are isomorphous, with the ethanol component disordered across a twofold rotation axis in the space group C2/c. In the corresponding 7‐[4‐(trifluoromethyl)benzyl]‐ compound, C31H34F3N3O2·0.5C2H6O, (IV), the ethanol component is disordered across a centre of inversion in the space group P. In each of (I)–(IV), the reduced pyridine ring adopts a half‐chair conformation. The heterocyclic components in (I)–(III) are linked into centrosymmetric dimers by a single C—H...π interaction, with the half‐occupancy ethanol component linked to the dimer by a combination of C—H...O and O—H...π(arene) hydrogen bonds. The heterocyclic molecules in (IV) are linked into chains of centrosymmetric rings by C—H...O and C—H...π hydrogen bonds, again with the half‐occupancy ethanol component pendent from the chain. The significance of this study lies in the isomorphism of the related derivatives (I)–(III), in the stoichiometric hemisolvation by ethanol, where the disordered solvent molecule is linked to the heterocyclic component by a two‐point linkage, and in the differences between the crystal structures of (I)–(III) and that of (IV). 相似文献
6.
Ashokkumar Subashini Kandasamy Ramamurthi Helen Stoeckli‐Evans 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(10):o408-o412
The 4‐chloro‐ [C14H11ClN2O2, (I)], 4‐bromo‐ [C14H10BrN2O2, (II)] and 4‐diethylamino‐ [C18H21N3O2, (III)] derivatives of benzylidene‐4‐hydroxybenzohydrazide, all crystallize in the same space group (P21/c), (I) and (II) also being isomorphous. In all three compounds, the conformation about the C=N bond is E. The molecules of (I) and (II) are relatively planar, with dihedral angles between the two benzene rings of 5.75 (12) and 9.81 (17)°, respectively. In (III), however, the same angle is 77.27 (9)°. In the crystal structures of (I) and (II), two‐dimensional slab‐like networks extending in the a and c directions are formed via N—H...O and O—H...O hydrogen bonds. The molecules stack head‐to‐tail viaπ–π interactions involving the aromatic rings [centroid–centroid distance = 3.7622 (14) Å in (I) and 3.8021 (19) Å in (II)]. In (III), undulating two‐dimensional networks extending in the b and c directions are formed via N—H...O and O—H...O hydrogen bonds. The molecules stack head‐to‐head viaπ–π interactions involving inversion‐related benzene rings [centroid–centroid distances = 3.6977 (12) and 3.8368 (11) Å]. 相似文献
7.
Anja Siegemund Christine Hartung Sven Baumann Brbel Schulze 《Helvetica chimica acta》2004,87(2):376-381
2‐Aryl‐4,5,6,7‐tetrahydro‐1,2‐benzisothiazol‐3(2H)‐ones 1a – e were synthesized by cyclocondensation of 2‐(thiocyanato)cyclohexene‐1‐carboxanilides 9 as a convenient new method. Their S‐oxides 10 were prepared by two routes, either by oxidation of 1 or dehydration of rac‐cis‐3‐hydroperoxysultims 11 . Furthermore, compounds 1 have been identified by HPLC? API‐MS‐MS as intermediates in the oxidation process of the salts 6 . The hydroperoxides 12b and rac‐trans‐ 11b have been unambiguously detected by HPLC? MS investigations and in the reaction of rac‐cis‐ 13b with H2O2 to the hydroperoxides rac‐trans‐ 11b and rac‐cis‐ 11b . 相似文献
8.
Ming‐Lin Guo Chen‐Hu Guo 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(10):m342-m344
In the title complex, {[Cd2(C8H3NO6)2(C4H10N2)(H2O)4]·2H2O}n, the CdII atoms show distorted octahedral coordination. The two carboxylate groups of the dianionic 2‐nitroterephthalate ligand adopt monodentate and 1,2‐bridging modes. The piperazine molecule is in a chair conformation and lies on a crystallographic inversion centre. The CdII atoms are connected via three O atoms from two carboxylate groups and two N atoms from piperazine molecules to form a two‐dimensional macro‐ring layer structure. These layers are further aggregated to form a three‐dimensional structure via rich intra‐ and interlayer hydrogen‐bonding networks. This study illustrates that, by using the labile CdII salt and a combination of 2‐nitroterephthalate and piperazine as ligands, it is possible to generate interesting metal–organic frameworks with rich intra‐ and interlayer O—H...O hydrogen‐bonding networks. 相似文献
9.
Ricaurte Rodríguez Justo Cobo Manuel Nogueras John N. Low Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(12):o643-o648
2‐Amino‐4‐methoxy‐6‐phenyl‐11H‐pyrimido[4,5‐b][1,4]benzodiazepine, C18H15N5O, (I), and its 6‐(2‐fluorophenyl)‐, 6‐(3‐nitrophenyl)‐ and 6‐(4‐methoxyphenyl)‐ analogues, viz. C18H14FN5O, (II), C18H14N6O3, (III), and C19H17N5O2, (IV), respectively, all adopt molecular conformations which are almost identical, containing boat‐shaped seven‐membered rings. In each structure, paired N—H...N hydrogen bonds link the molecules into centrosymmetric dimers. In each of (I)–(III), the dimers are further linked, forming a different three‐dimensional framework in each case, while in compound (IV) the dimers are linked into sheets. The significance of this study lies in the observation of different crystal structures in four compounds whose molecular structures are very similar. 相似文献
10.
Daniela Giardina‐Papa Francesco Paolo Intini Giovanni Natile Concetta Pacifico 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(11):m300-m302
The title compound, [PtCl(C3H7NO)2(C18H15P)]Cl·H2O or trans‐[PtCl{Z‐HN=C(Me)OMe}2(PPh3)]Cl·H2O, crystallizes from an acetone solution of isomeric trans‐[PtCl{E‐HN=C(Me)OMe}2(PPh3)]Cl. The two HN=C(Me)OMe ligands show typical π‐bond delocalization over the N—C—O group [Cini, Caputo, Intini & Natile (1995). Inorg. Chem. 34 , 1130–1137] and have the unprecedented Z–anti configuration. The relative orientation of the imino ether ligands is head‐to‐tail. 相似文献
11.
Coordination Chemistry of Highly Hemilabile Bidentate Sulfoxide N‐Heterocyclic Carbenes with Palladium(II) 下载免费PDF全文
Dr. Kuo‐Hsuan Yu Chia‐Ching Wang Dr. I‐Hsin Chang Yi‐Hung Liu Prof. Dr. Yu Wang Prof. Dr. Cornelis J. Elsevier Prof. Dr. Shiuh‐Tzung Liu Prof. Dr. Jwu‐Ting Chen 《化学:亚洲杂志》2014,9(12):3498-3510
Imidazolium salts, [RS(O)? CH2(C3H3N2)Mes]Cl (R=Me ( L1 a ), Ph ( L1 b )); Mes=mesityl), make convenient carbene precursors. Palladation of L1 a affords the monodentate dinuclear complex, [(PdCl2{MeS(O)CH2(C3H2N2)Mes})2] ( 2 a ), which is converted into trans‐[PdCl2(NHC)2] (trans‐ 4 a ; N‐heterocyclic carbene) with two rotamers in anti and syn configurations. Complex trans‐ 4 a can isomerize into cis‐ 4 a (anti) at reflux in acetonitrile. Abstraction of chlorides from 4 a or 4 b leads to the formation of a new dication: trans‐[Pd{RS(O)CH2(C3H2N2)Mes}2](PF6)2 (R=Me ( 5 a ), Ph ( 5 b )). The X‐ray structure of 5 a provides evidence that the two bidentate SO? NHC ligands at palladium(II) are in square‐planar geometry. Two sulfoxides are sulfur‐ and oxygen‐bound, and constitute five‐ and six‐membered chelate rings with the metal center, respectively. In acetonitrile, complexes 5 a or 5 b spontaneously transform into cis‐[Pd(NHC)2(NCMe)2](PF6)2. Similar studies of thioether–NHCs have also been examined for comparison. The results indicate that sulfoxides are more labile than thioethers. 相似文献
12.
Yue Feng Gang Liu Xiu‐Mei Tian Ji‐De Wang 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(12):m598-m600
In the title compound, [Cu(C9H5N2O2)2(H2O)2], the CuII ion lies on an inversion centre and has an elongated centrosymmetric octahedral environment, equatorially trans‐coordinated by two N,O‐bidentate quinoxaline‐2‐carboxylate ligands and axially coordinated by two water O atoms. Symmetry‐related molecules are linked by strong O—H...O hydrogen bonds, involving the uncoordinated carboxyl O atom of the carboxylate group and the coordinated water molecules, to form a two‐dimensional network. Weak intermolecular C—H...N interactions also stabilize the crystal structure. 相似文献
13.
Barbara Piotrkowska Tadeusz Pooski Maria Gdaniec 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(12):o693-o696
The bis‐thionooxalamic acid esters trans‐(±)‐diethyl N,N′‐(cyclohexane‐1,2‐diyl)bis(2‐thiooxamate), C14H22N2O4S2, and (±)‐N,N′‐diethyl (1,2‐diphenylethane‐1,2‐diyl)bis(2‐thiooxamate), C22H24N2O4S2, both consist of conformationally flexible molecules which adopt similar conformations with approximate C2 rotational symmetry. The thioamide and ester parts of the thiooxamate group are significantly twisted along the central C—C bond, with the S=C—C=O torsion angles in the range 30.94 (19)–44.77 (19)°. The twisted s‐cis conformation of the thionooxamide groups facilitates assembly of molecules into a one‐dimensional polymeric structure via intermolecular three‐center C=S...NH...O=C hydrogen bonds and C—H...O interactions formed between molecules of the opposite chirality. 相似文献
14.
Wu‐Wu Li Zun‐Ting Zhang 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(4):m176-m178
The title compound, [Co(H2O)6](C16H11O7S)2·4H2O, with cobalt(II) at the centre of symmetry, exhibits alternating hydrophilic and hydrophobic regions. Hydrophilic regions are generated by O—H...O hydrogen bonds among sulfonate groups, involving solvent water molecules and coordinated water molecules; π–π stacking interactions assemble the flavone skeletons into columns which form the hydrophobic regions. A three‐dimensional network is built up from an extensive array of hydrogen bonds, π–π stacking interactions and electrostatic interactions between the cation and anion. As a salt of the sulfonated derivative of naturally occurring tectochrysin (5‐hydroxy‐7‐methoxyflavone), this compound offers enhanced solubility and potential biological activity over the natural product. 相似文献
15.
Paul V. Bernhardt Nathan L. Kilah 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(5):m245-m249
The pendent‐arm macrocyclic hexaamine trans‐6,13‐dimethyl‐1,4,8,11‐tetraazacyclotetradecane‐6,13‐diamine (L) may coordinate in tetra‐, penta‐ or hexadentate modes, depending on the metal ion and the synthetic procedure. We report here the crystal structures of two pseudo‐octahedral cobalt(III) complexes of L, namely sodium trans‐cyano(trans‐6,13‐dimethyl‐1,4,8,11‐tetraazacyclotetradecane‐6,13‐diamine)cobalt(III) triperchlorate, Na[Co(CN)(C13H30N6)](ClO4)3 or Na{trans‐[CoL(CN)]}(ClO4)3, (I), where L is coordinated as a pentadentate ligand, and trans‐dicyano(trans‐6,13‐dimethyl‐1,4,8,11‐tetraazacyclotetradecane‐6,13‐diamine)cobalt(III) trans‐dicyano(trans‐6,13‐dimethyl‐1,4,8,11‐tetraazacyclotetradecane‐6,13‐diaminium)cobalt(III) tetraperchlorate tetrahydrate, [Co(CN)2(C14H32N6)][Co(CN)2(C14H30N6)](ClO4)4·4H2O or trans‐[CoL(CN)2]trans‐[Co(H2L)(CN)2](ClO4)4·4H2O, (II), where the ligand binds in a tetradentate mode, with the remaining coordination sites being filled by C‐bound cyano ligands. In (I), the secondary amine Co—N bond lengths lie within the range 1.944 (3)–1.969 (3) Å, while the trans influence of the cyano ligand lengthens the Co—N bond length of the coordinated primary amine [Co—N = 1.986 (3) Å]. The Co—CN bond length is 1.899 (3) Å. The complex cations in (II) are each located on centres of symmetry. The Co—N bond lengths in both cations are somewhat longer than in (I) and span a narrow range [1.972 (3)–1.982 (3) Å]. The two independent Co—CN bond lengths are similar [1.918 (4) and 1.926 (4) Å] but significantly longer than in the structure of (I), again a consequence of the trans influence of each cyano ligand. 相似文献
16.
Joshua P. Myers Frank R. Fronczek Thomas Junk 《Acta Crystallographica. Section C, Structural Chemistry》2016,72(1):1-5
There is a paucity of data concerning the structures of six‐ and seven‐membered tellurium‐ and nitrogen‐containing (Te—N) heterocycles. The title compounds, C8H7NOTe, (I), and C9H9NOTe, (II), represent the first structurally characterized members of their respective classes. Both crystallize with two independent molecules in the asymmetric unit. When compared to their sulfur analogs, they exhibit slightly greater deviations from planarity to accommodate the larger chalcogenide atom, with (II) adopting a pronounced twist‐boat conformation. The C—Te—C angles of 85.49 (15) and 85.89 (15)° for the two independent molecules of (I) were found to be somewhat smaller than those of 97.4 (2) and 97.77 (19)° for the two independent molecules of (II). The C—Te bond lengths [2.109 (4)–2.158 (5) Å] are in good agreement with those predicted by the covalent radii. Intermolecular N—H...O hydrogen bonding in (I) forms centrosymmetric R22(8) dimers, while that in (II) forms chains. In addition, intermolecular Te...O contacts [3.159 (3)–3.200 (3) Å] exist in (I). 相似文献
17.
Joanna Ruszkowska Robert Chrobak Jan K. Maurin Zbigniew Czarnocki 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(5):o377-o380
Vindoline, C25H32N2O6, and 16‐demethoxyvindoline, C24H30N2O5, both of which are naturally occurring biologically active products derived from plants, are important as possible starting materials for the synthesis of valuable anticancer antibiotics, viz. vincristine and vinblastine, and other pharmaceuticals. The vindoline framework consists of two five‐ and three six‐membered condensed rings. One of the six‐membered rings adopts a boat conformation, one adopts a sofa conformation and the third is planar. Both five‐membered rings have envelope structures. The intramolecular hydrogen bonds present in the structures are characteristic of vinca alkaloids. 相似文献
18.
Douglas M. Ho Michael E. Berardini Georgia M. Arvanitis 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(10):m391-m394
The complex trans‐bis(hinokitiolato)copper(II) [systematic name: trans‐bis(3‐isopropyl‐7‐oxocyclohepta‐1,3,5‐trienolato)copper(II); abbreviated name: trans‐Cu(hino)2], [Cu(C10H11O2)2], is a biologically active compound. Three polymorphs of this square‐planar monomer, all with (+sp,−sp) isopropyl substituents, have been reported previously. A fourth polymorph containing (+ac,−ac) isopropyl groups and its chloroform disolvate, [Cu(C10H11O2)2]·2CHCl3, both exhibiting nonmerohedral twinning and with all Cu atoms on centers of crystallographic inversion symmetry, are reported here. One of the differences between all of these polymorphs is the relative conformation of the isopropyl groups with respect to the plane of the molecule. Stacking and Cu...olefin π distances ranging from 3.214 (4) to 3.311 (2) Å are observed, and the chloroform solvent molecules participate in bifurcated C—H...O hydrogen bonds [H...O = 2.26–2.40 Å, C...O = 3.123 (5)–3.214 (5) Å, C—H...O = 127–151° and O...H...O = 74°]. 相似文献
19.
Liang Chen Renjie Liu Xiang Hao Qiang Yan 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(1):270-274
The design of structurally dynamic molecular networks can offer strategies for fabricating stimuli‐responsive adaptive materials. Herein we first report a gas‐responsive dynamic gel system based on frustrated Lewis pair (FLP) chemistry. Two trefoil‐like molecules with bulky triphenylborane and triphenylphosphine groups are synthesized as complementary Lewis acid and base with trivalent sites. They can together bind CO2 gas molecules and further form a cross‐linked network via the bonding interactions between FLPs and CO2. Such CO2‐bridged dative linkages are shown to be dynamic covalent bonds, which endow the frustrated Lewis network with adaptable behaviors and unprecedented gas‐regulated viscoelastic, mechanical, and self‐healing performance. This study is an initial attempt to apply the FLP concept in materials chemistry, but we believe that this strategy will open a promising future for gas‐sensitive smart materials. 相似文献
20.
Yoshitaro Miyashita Tetuya Ohashi Akiomi Imai Nagina Amir Kiyoshi Fujisawa Ken‐ichi Okamoto 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(11):m476-m478
The complex molecule in the title compound, [Re(C9H6NS)Cl2O(C18H15OP)]·C3H6O, has distorted octahedral geometry. The Re=O bond occupies the position trans to the triphenylphosphine oxide O atom. The Re—Cl bond trans to the thiolate S atom is longer than that trans to the quinoline N atom, implying a stronger trans influence of the S atom. Intra‐ and intermolecular π–π interactions are also observed between the π rings in the complex. 相似文献