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1.
Masashi Eto Koji Setoguchi Akiko Harada Eri Sugiyama Kazunobu Harano 《Tetrahedron letters》1998,39(52):6813
A series of crystalline host compounds, which have a bicyclo[2.2.1]heptene-7-one system, has been synthesized and their inclusion behavior has been investigated. The cycloadduct of phencyclone and N-naphthylmaleimide forms a 1:1 crystalline inclusion complex with 2-butanone. The crystal structure indicates the presence of weak lattice forces supported by CH···π and CH···O interactions. 相似文献
2.
Interaction of aromatic units of amino acids with guanidinium cation: The interplay of π···π, XH···π, and M+···π contacts 下载免费PDF全文
Alba Campo‐Cacharrón Enrique M. Cabaleiro‐Lago Jorge A. Carrazana‐García Jesús Rodríguez‐Otero 《Journal of computational chemistry》2014,35(17):1290-1301
Complexes formed by guanidinium cation and a pair of aromatic molecules among benzene, phenol, or indole have been computationally studied to determine the characteristics of the cation···π interaction in ternary systems modeling amino acid side chains. Guanidinium coordinates to the aromatic units preferentially in the following order: indole, phenol, and benzene. Complexes containing two different aromatic units show an intermediate behavior between that observed for complexes with only one kind of aromatic unit. Most stable structures correspond to doubly‐T shaped arrangements with the two aromatic units coordinating guanidinium by its NH2 groups. Other structures with only one aromatic unit coordinated to guanidinium, such as T‐shaped or parallel‐stacked ones, are less favorable but still showing significant stabilization. In indole and phenol complexes, the formation of hydrogen bonds between the aromatic molecules introduces extra stabilization in T‐shaped structures. Three body effects are small and repulsive in doubly T‐shaped minima. Only when hydrogen bonds involving the aromatic molecules are formed in T‐shaped structures a cooperative effect can be observed. In most complexes the interaction is controlled by electrostatics, with induction and dispersion also contributing significantly depending on the nature and orientation of the aromatic species forming the complex. Although the stability in these systems is mainly controlled by the intensity of the interaction between guanidinium and the aromatic molecules coordinated to it, interactions between aromatic molecules can modulate the characteristics of the complex, especially when hydrogen bonds are formed. © 2014 Wiley Periodicals, Inc. 相似文献
3.
《无机化学与普通化学杂志》2018,644(2):82-85
Using ferrocenecarboxylic acid (FcCOOH) as organometallic ligand in the synthesis of heterometallic complexes led to the isolation of the compound [(FcCOO)Cu(bpy)2](BF4) · bpy · CH3OH. It was characterized by IR spectroscopy, EA, powder XRD, UV, and TGA measurements. Single‐crystal X‐ray structural analysis revealed that a unique 2D supramolecular network purely formed by aromatic π ··· π stacking interactions was observed, namely, {[(FcCOO)Cu(bpy)2](BF4) · bpy · CH3OH}∞ ( 1 ). The solid UV/Vis diffuse reflectance spectrum revealed the optical energy gap of 1 to be 3.54 eV, which is dramatically blue shifted compared with the value of ferrocene. Experimental results of thermal analysis and electrochemical analysis show that 1 has good thermal and better electrochemical stability. 相似文献
4.
Yuan‐Xin Wei Hai‐Bei Li Jian‐Bo Cheng Wen‐Zuo Li Qing‐Zhong Li 《International journal of quantum chemistry》2017,117(23)
The potential applications of tetrel bonds involving π‐molecules in crystal materials and biological systems have prompted a theoretical investigation of the strength of π···σ‐hole tetrel bond in the systems with acetylene and its derivatives of CH3, AuPH3, Li, and Na as well as benzene as the π electron donors. A weak tetrel bond (ΔE < 15 kJ/mol) is found between acetylene and tetrel donor molecule TH3F (T = C, Si, Ge, Sn, and Pb). All substituents strengthen the π tetrel bond, but the electron‐donating sodium atoms have the largest enhancing effect and the interaction energy is up to about 24 kJ/mol in C2Na2‐CH3F. The electron‐donating ability of the AuPH3 fragment is intermediate between the methyl group and alkali metal atom. The origin of the stability of the π tetrel‐bonded complex is dependent on the nature of the tetrel donor and acceptor molecules and can be regulated by the substituents. 相似文献
5.
Jin‐Feng Mei Xiao‐Yong Jia Jian‐Cheng Lai Yang Sun Cheng‐Hui Li Jun‐Hua Wu Yi Cao Xiao‐Zeng You Zhenan Bao 《Macromolecular rapid communications》2016,37(20):1667-1675
A new self‐healing polymer has been obtained by incorporating a cyclometalated platinum(II) complex Pt(C∧N∧N)Cl (C∧N∧N = 6‐phenyl‐2,2′‐bipyridyl) into a polydimethylsiloxane (PDMS) backbone. The molecular interactions (a combination of Pt···Pt and π–π interactions) between cyclometalated platinum(II) complexes are strong enough to crosslink the linear PDMS polymer chains into an elastic film. The as prepared polymer can be stretched to over 20 times of its original length. When damaged, the polymer can be healed at room temperature without any healants or external stimuli. Moreover, the self‐healing is insensitive to surface aging. This work represents the first example where the attractive metallophilic interactions are utilized to design self‐healing materials. Moreover, our results suggest that the stretchability and self‐healing properties can be obtained simultaneously without any conflict by optimizing the strength of crosslinking interactions.
6.
《Journal of computational chemistry》2017,38(10):730-739
Noncovalent interactions involving aromatic rings, such as π···π stacking, CH···π are very essential for supramolecular carbon nanostructures. Graphite is a typical homogenous carbon matter based on π···π stacking of graphene sheets. Even in systems not involving aromatic groups, the stability of diamondoid dimer and layer‐layer graphane dimer originates from C − H···H − C noncovalent interaction. In this article, the structures and properties of novel heterogeneous layer‐layer carbon‐nanostructures involving π···H‐C‐C‐H···π···H‐C‐C‐H stacking based on [n ]‐graphane and [n ]‐graphene and their derivatives are theoretically investigated for n = 16–54 using dispersion corrected density functional theory B3LYP‐D3 method. Energy decomposition analysis shows that dispersion interaction is the most important for the stabilization of both double‐ and multi‐layer‐layer [n ]‐graphane@graphene. Binding energy between graphane and graphene sheets shows that there is a distinct additive nature of CH···π interaction. For comparison and simplicity, the concept of H‐H bond energy equivalent number of carbon atoms (noted as NHEQ), is used to describe the strength of these noncovalent interactions. The NHEQ of the graphene dimers, graphane dimers, and double‐layered graphane@graphene are 103, 143, and 110, indicating that the strength of C‐H···π interaction is close to that of π···π and much stronger than that of C‐H···H‐C in large size systems. Additionally, frontier molecular orbital, electron density difference and visualized noncovalent interaction regions are discussed for deeply understanding the nature of the C‐H···π stacking interaction in construction of heterogeneous layer‐layer graphane@graphene structures. We hope that the present study would be helpful for creations of new functional supramolecular materials based on graphane and graphene carbon nano‐structures. © 2017 Wiley Periodicals, Inc. 相似文献
7.
Fluorenyl Zinc Phosphonate Zn(H2O)PO3–C13H9·H2O: Hybrid Columnar Structure with Strong C–H···π Interactions 下载免费PDF全文
Clarisse Bloyet Jean‐Michel Rueff Vincent Caignaert Jean‐François Lohier Julien Cardin Paul‐Alain Jaffrès Bernard Raveau 《无机化学与普通化学杂志》2017,643(3):250-255
A new zinc phosphonate Zn(H2O)PO3–C13H9 · H2O with a columnar structure was synthesized in hydrothermal conditions. This compound crystallizes in space group P21/c [a = 15.832(4) Å, b = 5.1915(10) Å, c = 17.519(4) Å and β = 114.479(6)°]. Its inorganic framework consists of isolated chains of corner‐sharing ZnO3(H2O) and PO3C tetrahedra. These chains are linked to fluorene cycles, forming hybrid columns, interconnected through C–H ··· π bonds. The photoluminescence properties of this hybrid material show that its emission bands are red shifted with respect to those of the mother phosphonic acid. This effect is explained on the basis of the structural constraints imposed by the inorganic Zn‐phosphonate chains. 相似文献
8.
Philip J. Cox Marcel Jaspars Yashodharan Kumarasamy Lutfun Nahar Satyajit D. Sarker Mohammad Shoeb 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(9):o520-o522
The crystal structure of 9‐(3‐methylbut‐2‐enyloxy)‐7H‐furo[3,2‐g]chromen‐7‐one–4‐methoxy‐9‐(3‐methylbut‐2‐enyloxy)‐7H‐furo[3,2‐g]chromen‐7‐one (0.926/0.074), 0.926C16H14O4·0.074C17H16O5, is characterized by two independent imperatorin molecules in the asymmetric unit, which exhibit different side‐chain conformations. A small amount of phellopterin overlaps with one of the two imperatorin molecules. The supramolecular structure is supported by C—H...O, C—H...π and π–π interactions. 相似文献
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10.
《International journal of quantum chemistry》2018,118(8)
The intermolecular π‐hole···π‐electrons interactions between F2ZO (Z = C, Si, Ge) molecules and unsaturated hydrocarbons including acetylene, ethylene, 1,3‐butadiene and benzene were constructed to reveal the differences of tetrel bonds forming by carbon and heavier tetrel atoms. The ab initio computation in association with topological analysis of electron density, natural bond orbital, and energy decomposition analysis demonstrate that the strength of Si···π and Ge···π tetrel bonds is much stronger than that of C···π tetrel bonds. The Si···π and Ge···π tetrel bonds exhibit covalent or partially covalent interaction nature, while the weak C···π tetrel bonds display the hallmarks of noncovalent interaction, the electrostatic interaction is the primary influencing factor. The Si···π and Ge···π interactions are determined by both the σ‐ and π‐electron densities, while the C···π interactions are dominated mainly by the π‐electron densities. The π‐hole···π‐electrons tetrel bonds are dominated by electrostatic interaction, and polarization has a comparable contribution in the Si···π and Ge···π tetrel bonds. 相似文献
11.
Roser Pons Cristina Ibez Ana B. Buades Antonio Franconetti Angel Garcia‐Raso Juan J. Fiol Angel Terrn Elies Molins Antonio Frontera 《应用有机金属化学》2019,33(6)
We report the synthesis and X‐ray characterization of the N6‐benzyl‐N6‐methyladenine ligand (L) and three metal complexes, namely [Zn(HL)Cl3]·H2O ( 1 ), [Cd(HL)2Cl4] ( 2 ) and [H2L]2[Cd3(μ‐L)2(μ‐Cl)4Cl6]·3H2O ( 3 ). Complex 1 consists of the 7H‐adenine tautomer protonated at N3 and coordinated to a tetrahedral Zn(II) metal centre through N9. The octahedral Cd(II) in complex 2 is N9‐coordinated to two N6‐benzyl‐N6‐methyladeninium ligands (7H‐tautomer protonated at N3) that occupy apical positions and four chlorido ligands form the basal plane. Compound 3 corresponds to a trinuclear Cd(II) complex, where the central Cd atom is six‐coordinated to two bridging μ‐L and four bridging μ‐Cl ligands. The other two Cd atoms are six‐coordinated to three terminal chlorido ligands, to two bridging μ‐Cl ligands and to the bridging μ‐L through N3. Essentially, the coordination patterns, degree of protonation and tautomeric forms of the nucleobase dominate the solid‐state architectures of 1 – 3 . Additionally, the hydrogen‐bonding interactions produced by the endocyclic N atoms and NH groups stabilize high‐dimensional‐order supramolecular assemblies. Moreover, energetically strong anion–π and lone pair (lp)–π interactions are important in constructing the final solid‐state architectures in 1 – 3 . We have studied the non‐covalent interactions energetically using density functional theory calculations and rationalized the interactions using molecular electrostatic potential surfaces and Bader's theory of atoms in molecules. We have particularly analysed cooperative lp–π and anion–π interactions in 1 and π+–π+ interactions in 3 . 相似文献
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Philip J. Cox Stephen M. MacManus 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(10):o603-o604
Molecules of the title compound, C13H9ClO2, contain an intramolecular O—H...O hydrogen bond, and the two aromatic rings are inclined at 57.02 (3)° with respect to one another. The crystal structure is supported by C—H...O, C—H...π and π–π interactions. 相似文献
14.
Understanding the Fundamental Role of π/π, σ/σ, and σ/π Dispersion Interactions in Shaping Carbon‐Based Materials 下载免费PDF全文
Dr. Mercedes Alonso Tatiana Woller Dr. Francisco J. Martín‐Martínez Dr. Julia Contreras‐García Prof. Paul Geerlings Prof. Frank De Proft 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(17):4931-4941
Noncovalent interactions involving aromatic rings, such as π‐stacking and CH/π interactions, are central to many areas of modern chemistry. However, recent studies proved that aromaticity is not required for stacking interactions, since similar interaction energies were computed for several aromatic and aliphatic dimers. Herein, the nature and origin of π/π, σ/σ, and σ/π dispersion interactions has been investigated by using dispersion‐corrected density functional theory, energy decomposition analysis, and the recently developed noncovalent interaction (NCI) method. Our analysis shows that π/π and σ/σ stacking interactions are equally important for the benzene and cyclohexane dimers, explaining why both compounds have similar boiling points. Also, similar dispersion forces are found in the benzene???methane and cyclohexane???methane complexes. However, for systems larger than naphthalene, there are enhanced stacking interactions in the aromatic dimers adopting a parallel‐displaced configuration compared to the analogous saturated systems. Although dispersion plays a decisive role in stabilizing all the complexes, the origin of the π/π, σ/σ, and σ/π interactions is different. The NCI method reveals that the dispersion interactions between the hydrogen atoms are responsible for the surprisingly strong aliphatic interactions. Moreover, whereas σ/σ and σ/π interactions are local, the π/π stacking are inherently delocalized, which give rise to a non‐additive effect. These new types of dispersion interactions between saturated groups can be exploited in the rational design of novel carbon materials. 相似文献
15.
Alexander S. Romanov Gary F. Angles Mikhail Yu. Antipin Tatiana V. Timofeeva 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(3):m69-m72
The structures of tricarbonyl(formylcyclopentadienyl)manganese(I), [Mn(C6H5O)(CO)3], (I), and tricarbonyl(formylcyclopentadienyl)rhenium(I), [Re(C6H5O)(CO)3], (II), were determined at 100 K. Compounds (I) and (II) both possess a carbonyl group in a trans position relative to the substituted C atom of the cyclopentadienyl ring, while the other two carbonyl groups are in almost eclipsed positions relative to their attached C atoms. Analysis of the intermolecular contacts reveals that the molecules in both compounds form stacks due to short attractive π(CO)...π(CO) and π(CO)...π interactions, along the crystallographic c axis for (I) and along the [201] direction for (II). Symmetry‐related stacks are bound to each other by weak intermolecular C—H...O hydrogen bonds, leading to the formation of the three‐dimensional network. 相似文献
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17.
The blue copper complex compounds [Cu(phen)2(C6H8O4)] · 4.5 H2O ( 1 ) and [(Cu2(phen)2Cl2)(C6H8O4)] · 4 H2O ( 2 ) were synthesized from CuCl2, 1,10‐phenanthroline (phen) and adipic acid in CH3OH/H2O solutions. [Cu(phen)2‐ (C6H8O4)] complexes and hydrogen bonded H2O molecules form the crystal structure of ( 1 ) (P1 (no. 2), a = 10.086(2) Å, b = 11.470(2) Å, c = 16.523(3) Å, α = 99.80(1)°, β = 115.13(1)°, γ = 115.13(1)°, V = 1617.5(5) Å3, Z = 2). The Cu atoms are square‐pyramidally coordinated by four N atoms of the phen ligands and one O atom of the adipate anion (d(Cu–O) = 1.989 Å, d(Cu–N) = 2.032–2.040 Å, axial d(Cu–N) = 2.235 Å). π‐π stacking interactions between phen ligands are responsible for the formation of supramolecular assemblies of [Cu(phen)2(C6H8O4)] complex molecules into 1 D chains along [111]. The crystal structure of ( 2 ) shows polymeric [(Cu2(phen)2Cl2)(C6H8O4)2/2] chains (P1 (no. 2), a = 7.013(1) Å, b = 10.376(1) Å, c = 11.372(3) Å, α = 73.64(1)°, β = 78.15(2)°, γ = 81.44(1)°, V = 773.5(2) Å3, Z = 1). The Cu atoms are fivefold coordinated by two Cl atoms, two N atoms of phen ligands and one O atom of the adipate anion, forming [CuCl2N2O] square pyramids with an axial Cl atom (d(Cu–O) = 1.958 Å, d(Cu–N) = 2.017–2.033 Å, d(Cu–Cl) = 2.281 Å; axial d(Cu–Cl) = 2.724 Å). Two square pyramids are condensed via the common Cl–Cl edge to centrosymmetric [Cu2Cl2N4O2] dimers, which are connected via the adipate anions to form the [(Cu2(phen)2Cl2)(C6H8O4)2/2] chains. The supramolecular 3 D network results from π‐π stacking interactions between the chains. H2O molecules are located in tunnels. 相似文献
18.
Cover Picture: Understanding the Fundamental Role of π/π, σ/σ, and σ/π Dispersion Interactions in Shaping Carbon‐Based Materials (Chem. Eur. J. 17/2014) 下载免费PDF全文
Dr. Mercedes Alonso Tatiana Woller Dr. Francisco J. Martín‐Martínez Dr. Julia Contreras‐García Prof. Paul Geerlings Prof. Frank De Proft 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(17):4841-4841
19.
Lei Gao Yanli Zeng Xueying Zhang Lingpeng Meng 《Journal of computational chemistry》2016,37(14):1321-1327
The σ‐hole of M2H6 (M = Al, Ga, In) and π‐hole of MH3 (M = Al, Ga, In) were discovered and analyzed, the bimolecular complexes M2H6···NH3 and MH3···N2P2F4 (M = Al, Ga, In) were constructed to carry out comparative studies on the group III σ‐hole interactions and π‐hole interactions. The two types of interactions are all partial‐covalent interactions; the π‐hole interactions are stronger than σ‐hole interactions. The electrostatic energy is the largest contribution for forming the σ‐hole and π‐hole interaction, the polarization energy is also an important factor to form the M···N interaction. The electrostatic energy contributions to the interaction energy of the σ‐hole interactions are somewhat greater than those of the π‐hole interactions. However, the polarization contributions for the π‐hole interactions are somewhat greater than those for the σ‐hole interactions. © 2016 Wiley Periodicals, Inc. 相似文献
20.
Zachary N. Vealey Brandon Q. Mercado Patrick H. Vaccaro 《Acta Crystallographica. Section C, Structural Chemistry》2016,72(10):730-737
Tropolone long has served as a model system for unraveling the ubiquitous phenomena of proton transfer and hydrogen bonding. This molecule, which juxtaposes ketonic, hydroxylic, and aromatic functionalities in a framework of minimal complexity, also has provided a versatile platform for investigating the synergism among competing intermolecular forces, including those generated by hydrogen bonding and aryl coupling. Small members of the troponoid family typically produce crystals that are stabilized strongly by pervasive π–π, C—H…π, or ion–π interactions. The organic salt (TrOH·iBA) formed by a facile proton‐transfer reaction between tropolone (TrOH) and isobutylamine (iBA), namely isobutylammonium 7‐oxocyclohepta‐1,3,5‐trien‐1‐olate, C4H12N+·C7H5O2−, has been investigated by X‐ray crystallography, with complementary quantum‐chemical and statistical‐database analyses serving to elucidate the nature of attendant intermolecular interactions and their synergistic effects upon lattice‐packing phenomena. The crystal structure deduced from low‐temperature diffraction measurements displays extensive hydrogen‐bonding networks, yet shows little evidence of the aryl forces (viz. π–π, C—H…π, and ion–π interactions) that typically dominate this class of compounds. Density functional calculations performed with and without the imposition of periodic boundary conditions (the latter entailing isolated subunits) documented the specificity and directionality of noncovalent interactions occurring between the proton‐donating and proton‐accepting sites of TrOH and iBA, as well as the absence of aromatic coupling mediated by the seven‐membered ring of TrOH. A statistical comparison of the structural parameters extracted for key hydrogen‐bond linkages to those reported for 44 previously known crystals that support similar binding motifs revealed TrOH·iBA to possess the shortest donor–acceptor distances of any troponoid‐based complex, combined with unambiguous signatures of enhanced proton‐delocalization processes that putatively stabilize the corresponding crystalline lattice and facilitate its surprisingly rapid formation under ambient conditions. 相似文献