Two novel supramolecular complexes [Cu（bpapa）（dhbd）]·CHaOH （1） and [Cu（bpapa）（ma）]·ma （2） （bpapa= bis[6-（2-pyridylamino）pyrid-2-yl]amine, dhbd=2,3-dihydroxybutanedioate dianion, ma=a-methacrylate） were rationally designed, synthesized and characterized by single crystal X-ray diffraction, IR, electronic spectroscopy and thermogravimetric analyses. Complex 1 was the first oligo-a-pyfidylamino complex based on hydroxypolycarboxylate and self-assembled into a 3D honeycomb configuration network with open channels and tubes containing 1D ladder-shaped double chains formed by hydrogen bonds and aromatic π-π stacking interactions. Complex 2 constructed a 2D supramolecular network extended by 1D chains from dimeric supramolecular synthon through noncovalent supramolecular interactions. In the two complexes, the chelating monohelical ligand adopted all-anti configuration. Density functional theory calculations were applied to 1 and 2. 相似文献
In our previous paper, we reported that a dimeric Zn2+ complex with a 2,2′‐bipyridyl linker (Zn2L1), cyanuric acid (CA), and a Cu2+ ion automatically assemble in aqueous solution to form 4:4:4 complex 3 , which selectively catalyzes the hydrolysis of mono(4‐nitrophenyl)phosphate (MNP) at neutral pH. Herein, we report that the use of barbital (Bar) instead of CA for the self‐assembly with Zn2L1 and Cu2+ induces 2:2:2 complexation of these components, and not the 4:4:4 complex, to form supramolecular complex 6 a , the structure and equilibrium characteristics of which were studied by analytical and physical measurements. The finding show that 6 a also accelerates the hydrolysis of MNP, similarly to 3 . Moreover, inspired by the crystal structure of 6 a , we prepared barbital units that contain functional groups on their side chains in an attempt to produce supramolecular phosphatases that possess functional groups near the Cu2(μ‐OH)2 catalytic core so as to mimic the catalytic center of alkaline phosphatase (AP). 相似文献
[(N3S3)Au(AuPMe3)2]2 ( 1 ) and [(N3S3)Au(AuPEt3)2]2 ( 2 ) were prepared by treating AuCl(PMe3) or AuCl(PEt3) with H3N3S3 upon deprotonation by trimethylamine to give respective Au6 supermolecules. Using dppm(AuCl)2 instead of AuCl(PMe3) or AuCl(PEt3) to react with H3N3S3 in a similar reaction condition led to a rare heptanuclear supermolecule of [(N3S3)2Au7(dppm)4]Cl ( 3 ). It is noted that besides short intramolecular gold(I)?gold(I) distances, both compounds 1 and 2 also show intermolecular gold(I)?gold(I) distances of 3.067(1) and 3.241(1) Å, resulting in two‐dimensional and one‐dimensional polymeric gold(I) solid, respectively. In fact, compound 1 shows a similar two‐dimensional polymeric gold(I) solid to that of the reported [(N3S3)Au(AuPPhMe2)2]2 with an intermolecular gold(I)?gold(I) distance of 3.130(2) Å. Significantly, these intermolecular gold(I)?gold(I) distances are well correlated with their cone angles and emission energies. For example, intermolecular gold(I)?gold(I) distances increase in the order of 3.067(1) Å < 3.130(2) Å < 3.241(1) Å for PMe3 (118°), PPhMe2 (122°), and PEt3 (132°), and their emission energies also increase in the order of 542 nm < 530 nm < 504 nm, respectively. This work highlights a very good correlation between intermolecular aurophilic interactions and emission energies for a series of Au6 supermolecules, where the cone angle plays a vital role in the self‐assembly process as well. Finally, the emissions for 1 – 3 are tentatively assigned to the S → Au charge‐transfer transition, whereas they are most probably modified by gold(I)?gold(I) interactions. 相似文献
On edge : Self‐assembled monolayers of a bis(hydrazone)‐based molecular grid physisorbed on graphite are studied by scanning tunneling microscopy (see picture). High order is attained at the supramolecular level by thermal annealing of the grid‐based films. A preferential edge‐on configuration of the molecular grid with respect to the substrate is found.
The helical organization of oligo‐p‐phenylene‐based organogelators has been investigated by atomic force microscopy, circular and vibrational circular dichroism, and Raman techniques. Whilst OPPs with more than two phenyl rings in the core self‐assemble into left‐handed helices, that with a biphenyl core shows an inversion of the supramolecular helicity depending on the formation conditions through the atropisomerism of the biphenyl central unit. The results presented herein outline a new example of kinetically controlled modulation of supramolecular helicity. 相似文献
A 1,1′‐binaphthyl‐based bis(pyridine) ligand ( 1 ) was prepared in racemic and enantiomerically pure form to study the formation of [Pd2( 1 )4] complexes upon coordination to palladium(II) ions with regard to the degree of chiral self‐sorting. The self‐assembly process proceeds in a highly selective narcissistic self‐recognition manner to give only homochiral supramolecular M2L4 cages, which were characterized by ESI‐MS, NMR, and electronic circular dichroism (ECD) spectroscopy, as well as by single‐crystal XRD analysis. 相似文献
Two 3,6‐bis(R‐1H‐1,2,3‐triazol‐4‐yl)pyridazines (R=mesityl, monodisperse (CH2 CH2O)12CH3) were synthesized by the copper(I)‐catalyzed azide–alkyne cycloaddition and self‐assembled with tetrakis(acetonitrile)copper(I) hexafluorophosphate and silver(I) hexafluoroantimonate in dichloromethane. The obtained copper(I) complexes were characterized in detail by time‐dependent 1D [1H, 13C] and 2D [1H‐NOESY] NMR spectroscopy, elemental analysis, high‐resolution ESI‐TOF mass spectrometry, and analytical ultracentrifugation. The latter characterization methods, as well as the comparison to analog 3,6‐di(2‐pyridyl)pyridazine (dppn) systems and their corresponding copper(I) and silver(I) complexes indicated that the herein described 3,6‐bis(1H‐1,2,3‐triazol‐4‐yl)pyridazine ligands form [2×2] supramolecular grids. However, in the case of the 3,6‐bis(1‐mesityl‐1H‐1,2,3‐triazol‐4‐yl)pyridazine ligand, the resultant red‐colored copper(I) complex turned out to be metastable in an acetone solution. This behavior in solution was studied by NMR spectroscopy, and it led to the conclusion that the copper(I) complex transforms irreversibly into at least one different metal complex species. 相似文献
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