Two N-Heterocyclic Carbene Silver(I) Cyclophanes: Synthesis, Structural Studies, and Recognition for p-Phenylenediamine
摘要:
The diimidazolium salt 1,5-bis[1-ethylimidazoliumylethoxy]naphthalene hexafluorophosphate (2) and the dibenzimidazolium salt 1,4-bis[1-(n-butyl)benzimidazoliumylethoxy]benzene hexafluorophosphate (4), as well as their N-heterocyclic carbene silver(I) cyclophanes [naphthalene(OCH(2)CH(2)imyEt)(2)Ag](2)(PF6)(2) (5) and [benzene(OCH2CH2-bimy(n)Bu)(2)Ag](2)(PF6)(2) (6), have been prepared and characterized. Each cation in complexes 5 and 6 contains a 30-membered macrometallacycle. In the crystal packing of 5 and 6, 3D architectures are formed via intermolecular weak interactions, including pi-pi interactions, hydrogen bonds, and C-H center dot center dot center dot pi contacts. The recognition of neutral p-phenylenediamine (PDA) molecules using 5 and 6 as receptors via fluorescent and UV/vis spectroscopic titrations have been investigated.
Contrasting Self-Assembly and Gelation Properties among Bis-urea- and Bis-amide-Functionalised Dialkoxynaphthalene (DAN) π Systems
作者:Anindita Das、Suhrit Ghosh
DOI:10.1002/chem.201002208
日期:2010.12.10
Gelled together: Self‐assembly and gelation studies of bis‐urea‐ and bis‐amide‐functionalised dialkoxynaphthalene chromophores (DAN‐U and DAN‐A, respectively) revealed contrasting J‐ and H‐type aggregation properties in solution, respectively (see scheme). DAN‐U was found to be a “super‐gelator” with much higher thermal stability, whereas DAN‐A showed gelation with superior mechanical stability.
orthogonal self‐assembly of donor and acceptor chromophores has been demonstrated. Suitably designed 1,5‐dialkoxynaphthalene (DAN) and naphthalene tetracarboxylic acid diimide (NDI) derivatives were used as the donor and acceptor systems, respectively. The molecular design for self‐sorting relies upon the precise control over the placement of the self‐complementaryhydrogen‐bonding units (amide functionality)
Tetrathiafulvalenenaphthalenophanes: Planar Chirality and <i>cis</i><i>/</i><i>trans</i> Photoisomerization
作者:Roberto Ballardini、Vincenzo Balzani、Jan Becher、Alberto Di Fabio、Maria Teresa Gandolfi、Gunter Mattersteig、Mogens B. Nielsen、Françisco M. Raymo、Stuart J. Rowan、J. Fraser Stoddart、Andrew J. P. White、David J. Williams
DOI:10.1021/jo0001941
日期:2000.6.1
different excitation wavelengths (406 and 313 nm). In both cases, the trans --> cis process (Phi = 0.20 at 406 nm) is much more efficient than the reverse cis --> trans process (Phi = 0.030 at 406 nm). Since the absorption spectra of the trans and cis isomers are different and the quantum yield of the trans --> cisphotoisomerization reaction depends on the excitation wavelength, the mole fraction of
Syntheses, structures and luminescent properties of six divalent metal terephthalate coordination polymers based on three new flexible bis(imidazole) ligands
84·122}8}2. A comparison of the six complexes shows that the coordination mode of the terephthalate plays a key role in the construction of the coordinationpolymers and the three N-containing ligands beautify and enrich the structures. In addition, the powder X-ray diffraction (PXRD), elemental analysis, IR, thermal stability and optical properties of all compounds were investigated.
Template-Directed Syntheses, Spectroscopic Properties, and Electrochemical Behavior of [n]Catenanes
作者:Peter R. Ashton、Virna Baldoni、Vincenzo Balzani、Christian G. Claessens、Alberto Credi、H. D. Andreas Hoffmann、Françisco M. Raymo、J. Fraser Stoddart、Margherita Venturi、Andrew J. P. White、David J. Williams
Catenanes composed of two, three, five, or seven interlocked macrocycles have been synthesized in yields ranging from 1 to 30%. Their template-directed syntheses rely on a series of cooperative noncovalent bonding interactions between π-electron rich 1,5-dioxynaphthalene ring systems and π-electron deficient bipyridinium units which are incorporated within the macrocyclic components. The interlocked