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1.
Int J Anal Chem ; 2023: 1771563, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37057128

RESUMEN

The harvest period of cultivated ginseng is generally 4-6 years. Ginseng flowers (GFs), the nonmedicinal parts, are usually removed every autumn, in which components are generally believed to stay unchanged with the increasing cultivation age. Recently, few documents were reported on the variation of volatile organic compounds (VOCs) and other components about ginseng flowers. This study had an insight into the variation of the chemical constituents with the cultivation ages through the comparison of the volatile organic compounds, gross ginsenosides, crude polysaccharide, and gross proteins of ginseng flowers from 3-, 4-, 5-, and 6-yr-old (GF3, GF4, GF5, and GF6) which were conducted by headspace solid-phase microextraction-gas chromatography-triple quadrupole mass spectrometry (HS-SPME-GC-QQQ/MS) and spectroscopic analysis combined with multivariate statistical analysis, including one-way ANOVA analysis and T test. The results indicated that the crude polysaccharide contents raised significantly depending on cultivation age except 6-yr-old, whereas the gross ginsenosides and the gross protein content were indistinctive. According to the peak intensity of determined VOCs, the contents of most differential compounds arranged in an order from high to low are GF3, GF4, GF5, and GF6, such as the compounds 2-15, 17-19, 22, and 25-26, therefore, they can be inferred that they are important markers to identify the age of GFs. 461 common differential compounds were gained and 26 common volatile organic compounds were identified with RSI >800 and RI and RIx no more than 30, including alcohols (such as 11, 12, and 15), sesquiterpenes (such as 2, 3, and 4), esters (such as 1 and 26), naphthalene and naphthol (such as 7 and 20), which had potential effects on curing Alzheimer's disease, inflammatory diseases, and prostate cancer based on network pharmacology analysis. This paper firstly revealed the variation rules of constitutions of GFs, which may provide a reference for the harvest and making rational application.

2.
Hortic Res ; 10(9): uhad147, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37691964

RESUMEN

MicroTom has a short growth cycle and high transformation efficiency, and is a prospective model plant for studying organ development, metabolism, and plant-microbe interactions. Here, with a newly assembled reference genome for this tomato cultivar and abundant RNA-seq data derived from tissues of different organs/developmental stages/treatments, we constructed multiple gene co-expression networks, which will provide valuable clues for the identification of important genes involved in diverse regulatory pathways during plant growth, e.g. arbuscular mycorrhizal symbiosis and fruit development. Additionally, non-coding RNAs, including miRNAs, lncRNAs, and circRNAs were also identified, together with their potential targets. Interacting networks between different types of non-coding RNAs (miRNA-lncRNA), and non-coding RNAs and genes (miRNA-mRNA and lncRNA-mRNA) were constructed as well. Our results and data will provide valuable information for the study of organ differentiation and development of this important fruit. Lastly, we established a database (http://eplant.njau.edu.cn/microTomBase/) with genomic and transcriptomic data, as well as details of gene co-expression and interacting networks on MicroTom, and this database should be of great value to those who want to adopt MicroTom as a model plant for research.

3.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 5): m560, 2011 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-21754292

RESUMEN

The complex mol-ecule of the title compound, [Mn(C(13)H(10)N(4)O(8))(H(2)O)(2)] or [Mn(H(4)pbidc)(H(2)O)(2)] (H(6)pbidc = 2,2'-(propane-1,3-di-yl)bis-(1H-imidazole-4,5-dicarb-oxy-lic acid), has 2 symmetry with the twofold rotation axis running through the Mn(2+) cation and the central C atom of the propanediyl unit. The cation is six-coordinated by two N atoms and two O atoms from one H(4)pbidc(2-) anion and two water O atoms in a considerably distorted octa-hedral coordination. In the crystal, adjacent mol-ecules are linked through O-H⋯O and N-H⋯O hydrogen bonds into a three-dimensional network.

4.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 12): m1788, 2011 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-22199576

RESUMEN

In the title complex, bis-{µ-1-[(1H-benzimidazol-1-yl)meth-yl]-1H-1,2,4-triazole}disilver(I) dinitrate, [Ag(2)(C(10)H(9)N(5))(2)](NO(3))(2), the Ag(I) ion is nearly linearly coordinated [N-Ag-N angle is 155.72 (14)°] by two 1-[(1H-benzimidazole-1-yl)meth-yl]-1H-1,2,4-triazole (bmt) ligands. In addition, two bmt ligands link two Ag(I) ions, forming a dinuclear unit with an Ag⋯Ag distance of 5.0179 (15) Å. The whole complex is generated by an inversion centre. The dinuclear units and the NO(3) (-) counter-ions are connected by N-H⋯O hydrogen bonds and weak Ag⋯O inter-actions [2.831 (5), 2.887 (5) and 2.908 (5) Å], leading to a three-dimensional structure.

5.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 5): m578, 2010 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-21579058

RESUMEN

In the title complex, [Cd(2)(CH(3)COO)(2)Cl(2)(C(16)H(14)N(4))(CH(3)OH)(2)](n), the Cd(II) atom is six-coordinated by one N atom from a centrosymmetric bridging 1,2-bis-(2,2'-1H-benzimidazol-2-yl)ethane (bbe) ligand, two O atoms from a chelating acetate ligand, one O atom from a methanol mol-ecule and two bridging Cl atoms in a distorted octa-hedral geometry. The Cd(II) atoms are connected alternately by the Cl atoms and bbe ligands, leading to a chain along [001]. These chains are further linked by O-H⋯O hydrogen bonds. Intra-chain N-H⋯O hydrogen bonds are observed.

6.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 3): m340, 2010 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-21580272

RESUMEN

In the title salt, [Ag(C(9)H(8)N(6))(2)]NO(3), the central Ag(I) atom is linearly coordinated by the N atoms [171.97 (8)°] from two 1-[(benzimidazol-1-yl)meth-yl]-1H-1,2,3,4-tetra-zole ligands. The benzimidazole rings in adjacent mol-ecules are parallel with an average inter-planar distance of 3.461 Å; adjacent mol-ecules are linked through N-H⋯O hydrogen bonds into a linear chain along the b-axis direction.

7.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 9): m1155, 2010 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-21588549

RESUMEN

In the title complex, [Cu(CH(3)COO)Cl(C(16)H(14)N(4))]·H(2)O, the Cu(II) ion is five-coordinated by two N atoms from a 2,2'-(ethane-1,2-di-yl)di-1H-benzimidazole ligand, two O atoms from a chelating acetate ligand and one terminal monodentate Cl atom in a distorted square-pyramidal geometry. In the crystal, adjacent mol-ecules are linked through O-H⋯Cl, N-H⋯Cl, N-H⋯O and O-H⋯O hydrogen bonds into a three-dimensional network.

8.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 11): m1483, 2010 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-21588898

RESUMEN

In the title complex, [Zn(SO(4))(C(9)H(8)N(6))(H(2)O)(4)]·2H(2)O, the Zn(II) ion is six-coordinated by one N atom from a 1-[(1H-1,2,3-benzotriazol-1-yl)meth-yl]-1H-1,2,4-triazole ligand and five O atoms from one monodentate sulfate anion and four water mol-ecules in a distorted octa-hedral geometry. The sulfate tetra-hedron is rotationally disordered over two positions in a 0.618 (19):0.382 (19) ratio. In the crystal, adjacent mol-ecules are linked through O-H⋯O and O-H⋯N hydrogen bonds involving the cation, the anion, and the coordinated and uncoordinated water mol-ecules into a three-dimensional network.

9.
Acta Crystallogr C Struct Chem ; 75(Pt 8): 1065-1072, 2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-31380789

RESUMEN

Aminobenzoic acid derivatives are widely used in the preparation of new coordination polymers since they contain O-atom donors, as well as N-atom donors, and have a rich variety of coordination modes which can lead to polymers with intriguing structures and interesting properties. Two new coordination polymers incorporating 1-aminobenzene-3,4,5-tricarboxylic acid (H3abtc), namely, poly[(µ3-1-amino-5-carboxybenzene-3,4-dicarboxylato)diaquacadmium(II)], [Cd(C9H5NO6)(H2O)2]n, (I), and poly[[bis(µ5-1-aminobenzene-3,4,5-tricarboxylato)triaquatrizinc(II)] dihydrate], {[Zn3(C9H4NO6)2(H2O)3]·2H2O}n, (II), have been prepared and structurally characterized by single-crystal X-ray diffraction. In polymer (I), each tridentate 1-amino-5-carboxybenzene-3,4-dicarboxylate (Habtc2-) ligand coordinates to three CdII ions to form a two-dimensional network structure, in which all of the CdII ions and Habtc2- ligands are equivalent, respectively. Polymer (II) also exhibits a two-dimensional network structure, in which three crystallographically independent ZnII ions are bridged by two crystallographically independent pentadentate 1-aminobenzene-3,4,5-tricarboxylate (abtc3-) ligands. This indicates that changing the metal ion can influence the coordination mode of the H3abtc-derived ligand and further influence the detailed architecture of the polymer. Moreover, the IR spectra, thermogravimetric analyses and fluorescence properties were investigated.

10.
Acta Crystallogr C Struct Chem ; 75(Pt 8): 1142-1149, 2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-31380797

RESUMEN

Changing the pH value of a reaction system can result in polymers with very different compositions and architectures. Two new coordination polymers based on 1,1'-[1,4-phenylenebis(methylene)]bis(3,5-dicarboxylatopyridinium) (L2-), namely catena-poly[[[tetraaquacadmium(II)]-µ2-1,1'-[1,4-phenylenebis(methylene)]bis(3,5-dicarboxylatopyridinium)] 1.66-hydrate], {[Cd(C22H14N2O8)(H2O)4]·1.66H2O}n, (I), and poly[{µ6-1,1'-[1,4-phenylenebis(methylene)]bis(3,5-dicarboxylatopyridinium)}cadmium(II)], [Cd(C22H14N2O8)]n, (II), have been prepared in the presence of NaOH or HNO3 and structurally characterized by single-crystal X-ray diffraction. In polymer (I), each CdII ion is coordinated by two halves of independent L2- ligands, forming a one-dimensional chain structure. In the crystal, these chains are further connected through O-H...O hydrogen bonds, leading to a three-dimensional hydrogen-bonded network. In polymer (II), each hexadentate L2- ligand coordinates to six CdII ions, resulting in a three-dimensional network structure, in which all of the CdII ions and L2- ligands are equivalent, respectively. The IR spectra, thermogravimetric analyses and fluorescence properties of both reported compounds were investigated.

11.
Acta Crystallogr C Struct Chem ; 75(Pt 6): 643-649, 2019 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-31166915

RESUMEN

Compared with the monomorphic type of ligand, combining mixed ligands in one coordination polymer offers greater tunability of the structural framework. Employment of N-heterocyclic ligands and aromatic polycarboxylates is an effective approach for the construction of metal-organic frameworks (MOFs). Two new coordination polymers incorporating both 2-[(1H-imidazol-1-yl)methyl]-1H-benzimidazole (imb) and benzenedicarboxylic acid isomers, namely, catena-poly[[[di-µ-chlorido-bis[(2-carboxybenzoato-κ2O1,O1')cadmium(II)]]-bis{µ-2-[(1H-imidazol-1-yl)methyl]-1H-benzimidazole-κ2N:N'}] dihydrate], {[Cd(C8H5O4)Cl(C11H10N4)]·H2O}n, (I), and poly[[aqua(µ2-benzene-1,3-dicarboxylato-κ3O1,O1':O3){µ2-2-[(1H-imidazol-1-yl)methyl]-1H-benzimidazole-κ2N:N'}cadmium(II)] dihydrate], {[Cd(C8H4O4)(C11H10N4)(H2O)]·2H2O}n, (II), have been prepared and structurally characterized by single-crystal X-ray diffraction. In polymer (I), imb ligands bridge CdII ions, forming a one-dimensional chain, and 2-carboxybenzoate anions coordinate to the CdII ions in a terminal fashion. Polymer (II) exhibits a two-dimensional network structure in which imb ligands and the benzene-1,3-dicarboxylate anions join CdII ions co-operatively. This indicates that changing of the aromatic dicarboxylic acids can result in polymers with different compositions and architectures. Moreover, their IR spectra, PXRD (powder X-ray diffraction) patterns, thermogravimetric analyses and fluorescence properties were also investigated.

12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(4): 930-3, 2008 Apr.
Artículo en Zh | MEDLINE | ID: mdl-18619332

RESUMEN

Laser-induced plasma spectroscopy (LIPS) is characterized by its non-contact and real-time analysis. Its application to the determination of steel composition can meet the need of high-speed, continuous and automatic production in large steel companies. In the present article the minor elements concentrations of aluminum, manganese, cobalt, molybdenum, and titanium in a series of stainless steel 1Cr18Ni9Ti samples were determinate by laser-induced plasma spectroscopy, based on a Nd : YAG Q-switched solid laser with wavelength 1 064 nm as an exciting source and ICCD as detector. In the experiment the working delay time and gate time of ICCD were set suitably to get high signal-to-noise ratio emission spectral lines, and the internal standardization method related to matrix effect was used to deal with spectral data. Experiment results show that the concentration ratios of all the measured elements versus the reference element ferrum have a good linear relationship with the intensity ratios of them, the detection limits of the five tested elements are within 150 microg x g(-1).

13.
Acta Crystallogr C Struct Chem ; 74(Pt 5): 599-603, 2018 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-29726469

RESUMEN

In recent years, N-heterocyclic carboxylate ligands have attracted much interest in the preparation of new coordination polymers since they contain N-atom donors, as well as O-atom donors, and have a rich variety of coordination modes which can lead to polymers with intriguing structures and interesting properties. A new two-dimensional coordination polymer, namely poly[[µ3-2,2'-(1,2-phenylene)bis(4-carboxy-1H-imidazole-5-carboxylato)-κ6O4,N3,N3',O4':O5:O5']manganese(II)], [Mn(C16H8N4O8)]n or [Mn(H4Phbidc)]n, has been synthesized by the reaction of Mn(OAc)2·4H2O (OAc is acetate) with 2,2'-(1,2-phenylene)bis(1H-imidazole-4,5-dicarboxylic acid) (H6Phbidc) under solvothermal conditions. In the polymer, each MnII ion is six-coordinated by two N atoms from one H4Phbidc2- ligand and by four O atoms from three H4Phbidc2- ligands, forming a significantly distorted octahedral MnN2O4 coordination geometry. The MnII ions are linked by hexadentate H4Phbidc2- ligands, leading to a two-dimensional structure parallel to the ac plane. In the crystal, adjacent layers are further connected by N-H...O hydrogen bonds, forming a three-dimensional structure in the solid state.

14.
Acta Crystallogr C Struct Chem ; 73(Pt 8): 645-651, 2017 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-28776517

RESUMEN

Careful choice of the organic ligands is one of the most important parameters in the rational design and synthesis of coordination polymers. Aromatic polycarboxylates have been widely used in the preparation of metal-organic polymers since they can utilize various coordination modes to form diverse structures and can act as hydrogen-bond acceptors and donors in the assembly of supramolecular structures. Nitrogen-heterocyclic organic compounds have also been used extensively as ligands for the construction of polymers with interesting structures. In the polymers catena-poly[[[diaquabis{2-[(1H-imidazol-1-yl)methyl]-6-methyl-1H-benzimidazole-κN3}cobalt(II)]-µ2-benzene-1,4-dicarboxylato-κ2O1:O4] dihydrate], {[Co(C8H4O4)(C12H11N4)2(H2O)2]·2H2O}n, (I), and catena-poly[[[diaquabis{2-[(1H-imidazol-1-yl)methyl]-6-methyl-1H-benzimidazole-κN3}nickel(II)]-µ2-benzene-1,4-dicarboxylato-κ2O1:O4] dihydrate], {[Ni(C8H4O4)(C12H11N4)2(H2O)2]·2H2O}n, (II), the CoII or NiII ion lies on an inversion centre and exhibits a slightly distorted octahedral coordination geometry, coordinated by two N atoms from two imidazole rings and four O atoms from two monodentate carboxylate groups and two water molecules. The dicarboxylate ligands bridge metal ions forming a polymeric chain. The 2-[(1H-imidazol-1-yl)methyl]-6-methyl-1H-benzimidazole ligands coordinate to the CoII or NiII centres in monodentate modes through an imidazole N atom and are pendant on opposite sides of the main chain. The two structures are isomorphous. In the crystal, the one-dimensional chains are further connected through O-H...O, O-H...N and N-H...O hydrogen bonds, leading to a three-dimensional supramolecular architecture. In addition, the IR spectroscopic properties, PXRD patterns, thermogravimetric behaviours and fluorescence properties of both polymers have been investigated.

15.
Acta Crystallogr C Struct Chem ; 73(Pt 4): 314-318, 2017 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-28378714

RESUMEN

The unsymmetrical N-heterocyclic ligand 1-[(benzotriazol-1-yl)methyl]-1H-1,3-imidazole (bmi) has three potential N-atom donors and can act in monodentate or bridging coordination modes in the construction of complexes. In addition, the bmi ligand can adopt different coordination conformations, resulting in complexes with different structures due to the presence of the flexible methylene spacer. Two new complexes, namely bis{1-[(benzotriazol-1-yl)methyl]-1H-1,3-imidazole-κN3}dibromidomercury(II), [HgBr2(C10H9N5)2], and bis{1-[(benzotriazol-1-yl)methyl]-1H-1,3-imidazole-κN3}diiodidomercury(II), [HgI2(C10H9N5)2], have been synthesized through the self-assembly of bmi with HgBr2 or HgI2. Single-crystal X-ray diffraction shows that both complexes are mononuclear structures, in which the bmi ligands coordinate to the HgII ions in monodentate modes. In the solid state, both complexes display three-dimensional networks formed by a combination of hydrogen bonds and π-π interactions. The IR spectra and PXRD patterns of both complexes have also been recorded.

16.
Acta Crystallogr C Struct Chem ; 73(Pt 10): 828-832, 2017 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-28978791

RESUMEN

In the construction of coordination polymers, many factors can influence the formation of the final architectures, such as the nature of the metal centres, the organic ligands and the counter-anions. In the coordination polymer poly[aqua(µ-benzene-1,2-dicarboxylato-κ4O1,O1':O2,O2')[µ-2-(1H-imidazol-1-ylmethyl)-6-methyl-1H-benzimidazole-κ2N2:N3]cadmium(II)], [Cd(C12H12N4)(C8H4O4)(H2O)]n or [Cd(immb)(1,2-bdic)(H2O)]n, each CdII ion is seven-coordinated by two N atoms from two symmetry-related 2-(1H-imidazol-1-ylmethyl)-6-methyl-1H-benzimidazole (immb) ligands, by four O atoms from two symmetry-related benzene-1,2-dicarboxylate (1,2-bdic2-) ligands and by one water molecule, leading to a CdN2O5 distorted pentagonal bipyramidal coordination environment. The immb and 1,2-bdic2- ligands bridge CdII ions and form a two-dimensional network structure. O-H...O and N-H...O hydrogen bonds stabilize the structure. In addition, the IR spectroscopic properties, PXRD patterns, thermogravimetric behaviour and fluorescence properties of the title polymer have been investigated.

17.
Acta Crystallogr C Struct Chem ; 72(Pt 6): 480-4, 2016 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-27256695

RESUMEN

The N-heterocyclic ligand 2-[(1H-imidazol-1-yl)methyl]-1H-benzimidazole (imb) has a rich variety of coordination modes and can lead to polymers with intriguing structures and interesting properties. In the coordination polymer catena-poly[[cadmium(II)-bis[µ-benzene-1,2-dicarboxylato-κ(4)O(1),O(1'):O(2),O(2')]-cadmium(II)-bis{µ-2-[(1H-imidazol-1-yl)methyl]-1H-benzimidazole}-κ(2)N(2):N(3);κ(2)N(3):N(2)] dimethylformamide disolvate], {[Cd(C8H4O4)(C11H10N4)]·C3H7NO}n, (I), each Cd(II) ion exhibits an irregular octahedral CdO4N2 coordination geometry and is coordinated by four O atoms from two symmetry-related benzene-1,2-dicarboxylate (1,2-bdic(2-)) ligands and two N atoms from two symmetry-related imb ligands. Two Cd(II) ions are connected by two benzene-1,2-dicarboxylate ligands to generate a binuclear [Cd2(1,2-bdic)2] unit. The binuclear units are further connected into a one-dimensional chain by pairs of bridging imb ligands. These one-dimensional chains are further connected through N-H...O hydrogen bonds and π-π interactions, leading to a two-dimensional layered structure. The dimethylformamide solvent molecules are organized in dimeric pairs via weak interactions. In addition, the title polymer exhibits good fluorescence properties in the solid state at room temperature.

18.
Acta Crystallogr C Struct Chem ; 72(Pt 12): 1002-1006, 2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-27918303

RESUMEN

The synthesis of coordination polymers or metal-organic frameworks (MOFs) has attracted considerable interest owing to the interesting structures and potential applications of these compounds. It is still a challenge to predict the exact structures and compositions of the final products. A new one-dimensional coordination polymer, catena-poly[[[bis{1-[(1H-benzimidazol-2-yl)methyl]-1H-tetrazole-κN3}zinc(II)]-µ-hexane-1,6-dicarboxylato-κ4O1,O1':O6,O6'] monohydrate], {[Zn(C6H8O4)(C9H8N6)2]·H2O}n, has been synthesized by the reaction of Zn(Ac)2 (Ac is acetate) with 1-[(1H-benzimidazol-2-yl)methyl]-1H-tetrazole (bimt) and adipic acid (H2adi) at room temperature. In the polymer, each ZnII ion exhibits an irregular octahedral ZnN2O4 coordination geometry and is coordinated by two N atoms from two symmetry-related bimt ligands and four O atoms from two symmetry-related dianionic adipate ligands. ZnII ions are connected by adipate ligands into a one-dimensional chain which runs parallel to the c axis. The bimt ligands coordinate to the ZnII ions in a monodentate mode on both sides of the main chain. In the crystal, the one-dimensional chains are further connected through N-H...O hydrogen bonds, leading to a three-dimensional supramolecular architecture. In addition, the title polymer exhibits fluorescence, with emissions at 334 and 350 nm in the solid state at room temperature.

19.
Acta Crystallogr C Struct Chem ; 72(Pt 7): 530-5, 2016 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-27377273

RESUMEN

Metal-organic frameworks (MOFs) based on multidentate N-heterocyclic ligands involving imidazole, triazole, tetrazole, benzimidazole, benzotriazole or pyridine present intriguing molecular topologies and have potential applications in ion exchange, magnetism, gas sorption and storage, catalysis, optics and biomedicine. The 2-[(1H-1,2,4-triazol-1-yl)methyl]-1H-benzimidazole (tmb) ligand has four potential N-atom donors and can act in monodentate, chelating, bridging and tridentate coordination modes in the construction of complexes, and can also act as both a hydrogen-bond donor and acceptor. In addition, the tmb ligand can adopt different coordination conformations, resulting in complexes with helical structures due to the presence of the flexible methylene spacer. A new three-dimensional coordination polymer, poly[[bis(µ2-benzene-1,4-dicarboxylato)-κ(4)O(1),O(1'):O(4),O(4');κ(2)O(1):O(4)-bis{µ2-2-[(1H-1,2,4-triazol-1-yl)methyl-κN(4)]-1H-benzimidazole-κN(3)}dizinc(II)] trihydrate], {[Zn(C8H4O4)(C10H9N5)]·1.5H2O}n, has been synthesized by the reaction of ZnCl2 with tmb and benzene-1,4-dicarboxylic acid (H2bdic) under solvothermal conditions. There are two crystallographically distinct bdic(2-) ligands [bdic(2-)(A) and bdic(2-)(B)] in the structure which adopt different coordination modes. The Zn(II) ions are bridged by tmb ligands, leading to one-dimensional helical chains with different handedness, and adjacent helices are linked by bdic(2-)(A) ligands, forming a two-dimensional network structure. The two-dimensional layers are further connected by bdic(2-)(B) ligands, resulting in a three-dimensional framework with the topological notation 6(6). The IR spectra and thermogravimetric curves are consistent with the results of the X-ray crystal structure analysis and the title polymer exhibits good fluorescence in the solid state at room temperature.

20.
Acta Crystallogr C Struct Chem ; 72(Pt 11): 917-922, 2016 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-27811435

RESUMEN

Due to their strong coordination ability and the diversities of their coordination modes, N-heterocyclic organic compounds are used extensively as ligands for the construction of complexes with fascinating structures and potential applications in many fields. Two new complexes, namely bis{1-[(benzotriazol-1-yl)methyl]-1H-imidazole-κN3}dibromidozinc(II), [ZnBr2(C10H9N5)2], (I), and bis{1-[(benzotriazol-1-yl)methyl]-1H-imidazole-κN3}diiodidozinc(II), [ZnI2(C10H9N5)2], (II), have been synthesized by reaction of the unsymmetrical N-heterocyclic ligand 1-[(benzotriazol-1-yl)methyl]-1H-imidazole (bmi) with Zn(acetate)2 in the presence of KBr or KI. Single-crystal X-ray diffraction analysis shows that both complexes exhibit a mononuclear structure, in which the bmi ligands coordinate to the central metal ion in a monodentate mode. In the solid state, both complexes possess a three-dimensional network formed by hydrogen bonds and π-π interactions. In addition, the IR spectroscopic properties, PXRD patterns and fluorescence properties of both complexes have been investigated.

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