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1.
The condensation reaction of 2,2′‐diamino‐4,4′‐dimethyl‐6,6'‐dibromo‐1,1′‐biphenyl with 2‐hydroxybenzaldehyde as well as 5‐methoxy‐, 4‐methoxy‐, and 3‐methoxy‐2‐hydroxybenzaldehyde yields 2,2′‐bis(salicylideneamino)‐4,4′‐dimethyl‐6,6′‐dibromo‐1,1′‐biphenyl ( 1a ) as well as the 5‐, 4‐, and 3‐methoxy‐substituted derivatives 1b , 1c , and 1d , respectively. Deprotonation of substituted 2,2′‐bis(salicylideneamino)‐4,4′‐dimethyl‐1,1′‐biphenyls with diethylzinc yields the corresponding substituted zinc 2,2′‐bis(2‐oxidobenzylideneamino)‐4,4′‐dimethyl‐1,1′‐biphenyls ( 2 ) or zinc 2,2′‐bis(2‐oxidobenzylideneamino)‐4,4′‐dimethyl‐6,6′‐dibromo‐1,1′‐biphenyls ( 3 ). Recrystallization from a mixture of CH2Cl2 and methanol can lead to the formation of methanol adducts. The methanol ligands can either bind as Lewis base to the central zinc atom or as Lewis acid via a weak O–H ··· O hydrogen bridge to a phenoxide moiety. Methanol‐free complexes precipitate as dimers with central Zn2O2 rings.  相似文献   

2.
In the title complex, [Ag2Cd(CN)4(C12H12N2)2]·H2O or cis‐[Cd{Ag(CN)2}2(5,5′‐dmbpy)2]·H2O, where 5,5′‐dmbpy is 5,5′‐dimethyl‐2,2′‐bipyridyl, the asymmetric unit consists of a discrete neutral [Cd{Ag(CN)2}2(5,5′‐dmbpy)2] unit and a solvent water molecule. The CdII cation is coordinated by two bidentate chelate 5,5′‐dmbpy ligands and two monodentate [AgI(CN)2] anions, which are in a cis arrangement around the CdII cation, leading to an octahedral CdN6 geometry. The overall structure is stabilized by a combination of intermolecular hydrogen bonding, and AgI...AgI and π–π interactions, forming a three‐dimensional supramolecular network.  相似文献   

3.
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.  相似文献   

4.
π‐Conjugated organic materials exhibit high and tunable nonlinear optical (NLO) properties, and fast response times. 4′‐Phenyl‐2,2′:6′,2′′‐terpyridine (PTP) is an important N‐heterocyclic ligand involving π‐conjugated systems, however, studies concerning the third‐order NLO properties of terpyridine transition metal complexes are limited. The title binuclear terpyridine CoII complex, bis(μ‐4,4′‐oxydibenzoato)‐κ3O,O′:O′′;κ3O′′:O,O′‐bis[(4′‐phenyl‐2,2′:6′,2′′‐terpyridine‐κ3N,N′,N′′)cobalt(II)], [Co2(C14H8O5)2(C21H15N3)2], (1), has been synthesized under hydrothermal conditions. In the crystal structure, each CoII cation is surrounded by three N atoms of a PTP ligand and three O atoms, two from a bidentate and one from a symmetry‐related monodentate 4,4′‐oxydibenzoate (ODA2−) ligand, completing a distorted octahedral coordination geometry. Neighbouring [Co(PTP)]2+ units are bridged by ODA2− ligands to form a ring‐like structure. The third‐order nonlinear optical (NLO) properties of (1) and PTP were determined in thin films using the Z‐scan technique. The title compound shows a strong third‐order NLO saturable absorption (SA), while PTP exhibits a third‐order NLO reverse saturable absorption (RSA). The absorptive coefficient β of (1) is −37.3 × 10−7 m W−1, which is larger than that (8.96 × 10−7 m W−1) of PTP. The third‐order NLO susceptibility χ(3) values are calculated as 6.01 × 10−8 e.s.u. for (1) and 1.44 × 10−8 e.s.u. for PTP.  相似文献   

5.
A novel three‐dimensional coordination polymer, {[Pb(C14H8N2O4)(H2O)]·0.5C12H10N2}n, has been synthesized by hydrothermal reaction of Pb(OAc)2·3H2O (OAc is acetate), 2,2′‐(diazene‐1,2‐diyl)dibenzoic acid (H2L) and 1,2‐bis(pyridin‐4‐yl)ethylene (bpe). The asymmetric unit contains a crystallographically independent PbII cation, one L2− ligand, an aqua ligand and half a bpe molecule. Each PbII centre is seven‐coordinated by six O atoms of bridging–chelating carboxylate groups from L2− ligands and by one O atom from a coordinated water molecule. The PbII cations are bridged by L2− ligands, forming [PbO2]n chains along the a axis. These chains are further connected by L2− ligands along the b and c axes to give a three‐dimensional framework with a 41263 topology. The channel voids are occupied by bpe molecules.  相似文献   

6.
The original suggestion that a through-space mechanism was operative in the seven-bond J(P, P) coupling constant of 30.3 Hz observed for 3.3′-bis(1,1-dimethylethyl)-2,2′-[3,3′,5,5′-tetrakis(1,1-dimethylethyl)-1,1′-biphenyl-2,2′-diyl]bis(oxy)}bis[1,3,2-oxazaphospholidine] ( 1a )) was investigated. In the solid-state CP-MAS 31PNMR spectrum of 1a , two nonequivalent P -atoms were observed; sufficient resolution could not be obtained to determine whether P, P coupling was present. The preparation and spectral data of the N-methyl analogue 1b and of the acyclic N-isopropyl analogue 6 (Scheme 1) provided evidence that a) the essentially exclusive formation (R*, R*,S*)- 1a in the reaction of the disodium biphenyldiolate 3a with the phosphorochloridite 4a is the result of significant differences in the free energy of activation (ΔG*) for the formation of the various diastereoisomers due to the steric congestion within the molecule and that b) the magnitude of the observed P,P coupling is dependent upon the degree of conformational freedom within the molecule. In the 31P-NMR spectrum of the P-sulfide 7 , which was prepared by the reaction of la with sulfur, 2s resonances were observed that strongly suggested that the lone electrons pair on P are involved in the mechanism for the transmission of coupling data. The (4S,5R) -12 and (4R, 5S) -12 of la were prepared in a three-step reaction sequence starting from the corresponding enantiomerically pure norephredine 8 (Scheme 2). Both (4S, 5R)- and (4R, 5S) -12 were obtained as a diastereoisomer mixture that differ by the configuration of the axis of chirality, i.e., (R*R*,R*)- and (R*,S*,R*) -12 were obtained. The major diastereoisomer was obtained upon recrystallization, and the atropisomers were observed to equilibrate in solution by monitoring the H? C(5) resonance in the 1H-NMR with time (ΔG° = 0.4 kcal/mol; Fig. 2). The process observed corresponds to the restricted rotation about the central single bond of the biphenyl system. The isolation of an atropisomer with only a single ortho substituent on each aryl ring is quite rare. In the 13C-NMR spectrum of both (R*,R*,R*)- and (R*,S*,R*) -12 , C(5) is two-bond-coupled to the oxazaphospholidine P-atom (2J(C(5),P((2)) = 8.5 Hz) that is further virtually coupled to the P-atom of the other oxazaphospholidine ring (7J(P(2),P(2′)) = 30 Hz; 9J(C(5),P(2′)) = 0 Hz; δ(P(2)) = δ(P(2′)) = 136 ppm. In the 31P-NMR spectrum of (R*,R*,S*) -12 , which was prepared from the racemic chloridite (mixture of three diastereoisomers was obtained), a 7J(P(2),P(2′) of 36 Hz was observed. These observations provide strong evidence that seven-bond P,P coupling occurs in all three diastereoisomers of 12 . The observed P,P coupling is both independent of the configuration of the chiral axis and the configuration of the asymmetric P-centers. This independence of P,P coupling upon the configuration on P implies also the independence of the observed coupling upon the orientation of the lone-pair of electrons on P provided that the conformations of the diastereoisomers are similar in solution. The X-ray crystal structure of the complex formed from 1a and dichloro(cycloocta-1,5-diene)platinum(II) was obtained and the solid-state structure discussed. The major diastereoisomer of (4S,5R) -12 was used as a chiral ligand in asymmetric hydrosilylation and hydrogenation reactions (Scheme 3).  相似文献   

7.
In (C11H12N4)2ZnCl2, the zinc(II) center is coordinated by the pyridine nitrogen atoms of two 4‐[N,N‐bis(2‐cyanoethyl)amino]pyridine ligands and two chlorine atoms in a tetrahedral geometry. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

8.
The N4 donor ligand, Me2bpzb2? and a pyridine molecule are coordinated to the Zinc(II) so that the coordination geometry closely resembles a square‐pyramidal environment with a nitrogen atom of the pyridine ligand occupying the apical position. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

9.
In the title coordination polymer, [Zn2(C14H8N2O4)2(C12H10N2)]n, the asymmetric unit contains one ZnII cation, two halves of 2,2′‐(diazene‐1,2‐diyl)dibenzoate anions (denoted L2−) and half of a 1,2‐bis(pyridin‐4‐yl)ethene ligand (denoted bpe). The three ligands lie across crystallographic inversion centres. Each ZnII centre is four‐coordinated by three O atoms of bridging carboxylate groups from three L2− ligands and by one N atom from a bpe ligand, forming a tetrahedral coordination geometry. Two ZnII atoms are bridged by two carboxylate groups of L2− ligands, generating a [Zn2(CO2)2] ring. Each loop serves as a fourfold node, which links its four equivalent nodes via the sharing of four L2− ligands to form a two‐dimensional [Zn2L4]n net. These nets are separated by bpe ligands acting as spacers, producing a three‐dimensional framework with a 4664 topology. Powder X‐ray diffraction and solid‐state photoluminescence were also measured.  相似文献   

10.
In the title compound, [Fe(C10H8N2)3](C9H5N4O)2·2H2O, the chiral cations lie across twofold rotation axes in the space group C2/c. The anions and the water molecules are linked by two independent O—H...N hydrogen bonds to form C22(8) chains, and these chains are linked by the cations via C—H...N and C—H...O hydrogen bonds to form two interpenetrating three‐dimensional frameworks, each of which contains only one enantiomeric form of the chiral cation.  相似文献   

11.
Imidazole‐4,5‐dicarboxylic acid (H3IDC) and its derivatives are widely used in the preparation of new coordination polymers owing to their versatile bridging coordination modes and potential hydrogen‐bonding donors and acceptors. A new one‐dimensional coordination polymer, namely catena‐poly[[diaquacadmium(II)]‐μ3‐2,2′‐(1,2‐phenylene)bis(1H‐imidazole‐4,5‐dicarboxylato)], [Cd(C16H6N4O8)0.5(H2O)2]n or [Cd(H2Phbidc)1/2(H2O)2]n, has been synthesized by the reaction of Cd(OAc)2·2H2O (OAc is acetate) with 2,2′‐(1,2‐phenylene)bis(1H‐imidazole‐4,5‐dicarboxylic acid) (H6Phbidc) under solvothermal conditions. In the polymer, one type of Cd ion (Cd1) is six‐coordinated by two N atoms and two O atoms from one H2Phbidc4− ligand and by two O atoms from two water molecules, forming a significantly distorted octahedral CdN2O4 coordination geometry. In contrast, the other type of Cd ion (Cd2) is six‐coordinated by two N atoms and two O atoms from two symmetry‐related H2Phbidc4− ligands and by two O atoms from two symmetry‐related water molecules, leading to a more regular octahedral coordination geometry. The Cd1 and Cd2 ions are linked by H2Phbidc4− ligands into a one‐dimensional chain which runs parallel to the b axis. In the crystal, the one‐dimensional chains are connected through hydrogen bonds, generating a two‐dimensional layered structure parallel to the ab plane. Adjacent layers are further linked by hydrogen bonds, forming a three‐dimensional structure in the solid state.  相似文献   

12.
The title complex features a two‐dimensional polymeric structure owing to the presence of µ4‐bridging naphthalene‐1,4,5,8‐tetracarboxylate ligands. The trigonal bipyramidal coordination geometry for zinc is completed by a chelating 2,2′‐bipyridine and a water molecule. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

13.
The cadmium atom is coordinated in distorted pentagonal bipyramidal geometry by the pyridine‐nitrogen atom of the 4‐[N,N‐bis(2‐cyanoethyl)amino]pyridine ligand, two oxygen atoms of two methanol molecules and four oxygen atoms of two acetate groups. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

14.
Novel polyurethanes (PUs) based on 2,2′‐[ethane‐1,2‐diylbis(nitrilomethylylidene)]diphenol and 2,2′‐[hexane‐1,6‐diylbis(nitrilomethylylidene)]diphenol as hard segments containing four aromatic diisocyanates (4,4′‐diphenylmethane diisocyanate, toluene 2,4‐diisocyanate, isophorone diisocyanate, and hexamethylene diisocyanate) have been prepared. Fourier transform infrared, UV spectrophotometry, fluorescence spectroscopy, 1H NMR and 13C NMR spectroscopy, thermogravimetric analysis, and differential thermal analysis have been used to determine the structural characterization and thermal properties of the segmented PUs. All the PUs contain domains of both semicrystalline and amorphous structures, as indicated by X‐ray diffraction. The acoustic properties have been calculated with the group contribution method. Molecular dynamics simulations have been performed on all the PUs to estimate the cohesive energy density and solubility parameter values, which compare well with the values calculated with the group contribution method. Furthermore, the simulation protocols have been applied to the PUs to produce X‐ray diffraction plots to determine the phase morphology of the PUs. The surface properties of the PUs have been estimated from the simulation protocols. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6032–6046, 2006  相似文献   

15.
In the title compound, [Cu2(C19H24N2O4)2(H2O)2]·2H2O, the asymmetric unit consists of one half of the bis{μ‐6,6′‐dimethoxy‐2,2′‐[propane‐1,2‐diylbis(iminomethylene)]diphenolato}bis[aquacopper(II)] complex and two water molecules. Two CuII centres are bridged through a pair of phenolate groups, resulting in a complex with a centrosymmetric structure, with the centre of inversion at the middle of the Cu2O2 plane. The Cu atoms are in a slightly distorted square‐pyramidal coordination environment (τ = 0.07). The average equatorial Cu—O bond length and the axial Cu—O bond length are 1.928 (3) and 2.486 (3) Å, respectively. The Cu—O(water) bond length is 2.865 (4) Å, so the compound could be described as having a weakly coordinating water molecule at each CuII ion and two solvent water molecules per dimetallic unit. The Cu...Cu distance and Cu—O—Cu angle are 3.0901 (10) Å and 87.56 (10)°, respectively. The molecules are linked into a sheet by O—H...O and C—H...O hydrogen bonds parallel to the [001] plane.  相似文献   

16.
In the title coordination polymer, catena‐poly[[dichloridomanganese(II)]‐μ‐1,1‐diphenyl‐3,3′‐[(1R,2R)‐cyclohexane‐1,2‐diylbis(azaniumylylidene)]dibut‐1‐en‐1‐olate‐κ2O:O′], [MnCl2(C26H30N2)]n, synthesized by the reaction of the chiral Schiff base ligand 1,1‐diphenyl‐3,3′‐[(1R,2R)‐cyclohexane‐1,2‐diylbis(azanediyl)]dibut‐2‐en‐1‐one (L) with MnCl2·4H2O, the asymmetric unit contains one crystallographically unique MnII ion, one unique spacer ligand, L, and two chloride ions. Each MnII ion is four‐coordinated in a distorted tetrahedral coordination environment by two O atoms from two L ligands and by two chloride ligands. The MnII ions are bridged by L ligands to form a one‐dimensional chain structure along the a axis. The chloride ligands are monodentate (terminal). The ligand is in the zwitterionic enol form and displays intramolecular ionic N+—H...O hydrogen bonding and π–π interactions between pairs of phenyl rings which strengthen the chains.  相似文献   

17.
In the title coordination polymer, [Pb(C14H8N2O4)(CH3OH)2]n, the asymmetric unit contains half of a PbII cation, half of a 2,2′‐(diazene‐1,2‐diyl)dibenzoate dianionic ligand (denoted L2−) and one methanol ligand. Each PbII centre is eight‐coordinated by six O atoms of chelating/bridging carboxylate groups from four L2− ligands and two O atoms from two terminal methanol ligands, forming a distorted dodecahedron. The [PbL2(MeOH)2] subunits are interlinked via the sharing of two carboxylate O atoms to form a one‐dimensional [PbL2(MeOH)2]n chain. Adjacent chains are further connected by L2− ligands, giving rise to a two‐dimensional layer, and these layers are bridged by L2− linkers to afford a three‐dimensional framework with a 41263 topology.  相似文献   

18.
The title compound, C39H30O6·CDCl3, has a chemical threefold axis and an approximately planar structure, with an ethoxycarbonyl substituent on each of the terminal benzenes oriented in the same direction, thus forming a propeller‐shaped molecule. This molecule is of particular interest in the field of metal–organic frameworks (MOFs), where its hydrolyzed analogue forms MOF structures with high surface areas. The benzene ring which occupies the centre of the molecule forms π–π interactions to the equivalent benzene ring at a perpendicular distance of 3.32 (1) Å. Centrosymmetric dimers formed in this way are interconnected by intermolecular C—H...π interactions with a rather short H...CgA distance of 2.51 Å (CgA is the centroid of the central benzene ring). The molecules are arranged in regular parallel sheets. Within a sheet, molecules are interconnected via C—H...O interactions where all carbonyl O atoms participate in weak hydrogen bonds as hydrogen‐bond acceptors. Neighbouring sheets are connected through the above‐mentioned π–π and C—H...π interactions.  相似文献   

19.
The title coordination polymer, poly[[aqua(μ5‐1,1′‐biphenyl‐2,2′,5,5′‐tetracarboxylato)bis[μ2‐1,4‐bis(1H‐imidazol‐1‐yl)benzene]dicadmium(II)] dihydrate], {[Cd2(C16H6O8)(C12H10N4)2(H2O)]·2H2O}n, was crystallized from a mixture of 1,1′‐biphenyl‐2,2′,5,5′‐tetracarboxylic acid (H4bpta), 1,4‐bis(1H‐imidazol‐1‐yl)benzene (1,4‐bib) and cadmium nitrate in water–dimethylformamide. The crystal structure consists of two crystallographically independent CdII cations, with one of the CdII cations possessing a slightly distorted pentagonal bipyramidal geometry. The second CdII centre is coordinated by carboxylate O atoms and imidazole N atoms from two separate 1,4‐bib ligands, displaying a distorted octahedral CdN2O4 geometry. The completely deprotonated bpta4− ligand, exhibiting a new coordination mode, bridges five CdII cations to form one‐dimensional chains viaμ3‐η1212 and μ2‐η1100 modes, and these are further linked by 1,4‐bib ligands to form a three‐dimensional framework with a (42.64)(4.62)(43.65.72) topology. The structure of the coordination polymer is reinforced by intermolecular hydrogen bonding between carboxylate O atoms, aqua ligands and crystallization water molecules. The solid‐state photoluminescence properties were investigated and the complex might be a candidate for a thermally stable and solvent‐resistant blue fluorescent material.  相似文献   

20.
Two noble metal complexes involving ancillary chloride ligands and chelating 2,2′‐bipyridylamine (Hdpa) or its deprotonated derivative (dpa), namely [bis(pyridin‐2‐yl‐κN)amine]tetrachloridoplatinum(IV), [PtCl4(C10H9N3)], and [bis(pyridin‐2‐yl‐κN)aminido]dichloridogold(III), [AuCl2(C10H8N3)], are presented and structurally characterized. The metal atom in the former has a slightly distorted octahedral coordination environment, formed by four chloride ligands and two pyridyl N atoms of Hdpa, while the metal atom in the latter has a slightly distorted square‐planar coordination environment, formed by two chloride ligands and two pyridyl N atoms of dpa. The difference in conjugation between the pyridine rings in normal and deprotonated 2,2′‐dipyridylamine is discussed on the basis of the structural features of these complexes. The influence of weak interactions on the supramolecular structures of the complexes, providing one‐dimensional chains of [PtCl4(C10H9N3)] and dimers of [AuCl2(C10H8N3)], are discussed.  相似文献   

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