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101.
Nicola Y. Edwards David M. Schnable Ioana R. Gearba-Dolocan Jenna L. Strubhar 《Molecules (Basel, Switzerland)》2021,26(1)
Lanthanide complexes have been developed and are reported herein. These complexes were derived from a terpyridine-functionalized calix[4]arene ligand, chelated with Tb3+ and Eu3+. Synthesis of these complexes was achieved in two steps from a calix[4]arene derivative: (1) amide coupling of a calix[4]arene bearing carboxylic acid functionalities and (2) metallation with a lanthanide triflate salt. The ligand and its complexes were characterized by NMR (1H and 13C), fluorescence and UV-vis spectroscopy as well as MS. The photophysical properties of these complexes were studied; high molar absorptivity values, modest quantum yields and luminescence lifetimes on the ms timescale were obtained. Anion binding results in a change in the photophysical properties of the complexes. The anion sensing ability of the Tb(III) complex was evaluated via visual detection, UV-vis and fluorescence studies. The sensor was found to be responsive towards a variety of anions, and large binding constants were obtained for the coordination of anions to the sensor. 相似文献
102.
Annalena Gärtner Matthäus Marek Dr. Merle Arrowsmith Dr. Dominic Auerhammer Krzysztof Radacki Dr. Dominic Prieschl Dr. Rian D. Dewhurst Prof. Dr. Holger Braunschweig 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(37):9694-9699
Cyclic alkyl(amino)carbene-stabilized (cyano)hydroboryl anions were synthesized by deprotonation of (cyano)dihydroborane precursors. While they display boron-centered nucleophilic reactivity towards organohalides, generating fully unsymmetrically substituted cyano(hydro)organoboranes, they show cyano-nitrogen-centered nucleophilic reactivity towards haloboranes, resulting in the formation of hitherto unknown linear 2-aza-1,4-diborabutatrienes. 相似文献
103.
Dr. Andrey Belyaev Prof. Pi-Tai Chou Prof. Igor O. Koshevoy 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(2):537-552
Tunable electron-accepting properties of the cationic phosphorus center, its geometry and unique preparative chemistry that allows combining this unit with diversity of π-conjugated motifs, define the appealing photophysical and electrochemical characteristics of organophosphorus ionic chromophores. This Minireview summarizes the achievements in the synthesis of the π-extended molecules functionalized with P-cationic fragments, modulation of their properties by means of structural modification, and emphasizes the important effect of cation-anion interactions, which can drastically change physical behavior of these two-component systems. 相似文献
104.
Yuen Cheong Tse Dr. Robert Hein Edward J. Mitchell Zongyao Zhang Prof. Paul D. Beer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(58):14550-14559
Anion receptors employing two distinct sensory mechanisms are rare. Herein, we report the first examples of halogen-bonding porphyrin BODIPY [2]rotaxanes capable of both fluorescent and redox electrochemical sensing of anions. 1H NMR, UV/visible and electrochemical studies revealed rotaxane axle triazole group coordination to the zinc(II) metalloporphyrin-containing macrocycle component, serves to preorganise the rotaxane binding cavity and dramatically enhances anion binding affinities. Mechanically bonded, integrated-axle BODIPY and macrocycle strapped metalloporphyrin motifs enable the anion recognition event to be sensed by the significant quenching of the BODIPY fluorophore and cathodic perturbations of the metalloporphyrin P/P+. redox couple. 相似文献
105.
Characterization of multiple fragmentation pathways initiated by collision‐induced dissociation of multifunctional anions formed by deprotonation of 2‐nitrobenzenesulfonylglycine 下载免费PDF全文
Tara E. Tovstiga Elizabeth A. L. Gillis J. Stuart Grossert Robert L. White 《Journal of mass spectrometry : JMS》2014,49(2):168-177
The correlation of anion structure with the fragmentation behavior of deprotonated nitrobenzenesulfonylamino acids was investigated using tandem mass spectrometry, isotopic labeling and computational methods. Four distinct fragmentation pathways resulting from the collision‐induced dissociation (CID) of deprotonated 2‐nitrobenzenesulfonylglycine (NsGly) were characterized. The unusual loss of the aryl nitro substituent as HONO was the lowest energy process. Subsequent successive losses of CO, HCN and SO2 indicated that an ortho cyclization reaction had accompanied loss of HONO. Other pathways involving rearrangement of the ionized sulfonamide group, dual bond cleavage and intramolecular nucleophilic displacement were proposed to account for the formation of phenoxide, arylsulfinate and arylsulfonamide product ions at higher collision energies. The four distinct fragmentation pathways were consistent with precursor–product relationships established by CID experiments, isotopic labeling results and the formation of analogous product ions from 2,4‐dinitrobenzenesulfonylglycine and the Ns derivatives of alanine and 2‐aminoisobutyric acid. The computations confirmed a low barrier for ortho cyclization with loss of HONO and feasible energetics for each reaction step in the four pathways. Computations also indicated that three of the fragmentation pathways started from NsGly ionized at the carboxyl group. Overall, the pathways identified for the fragmentation of the NsGly anion differed from processes reported for anions containing a single functional group, demonstrating the importance of functional group interactions in the fragmentation pathways of multifunctional anions. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
106.
Dr. Nicholas H. Evans Prof. Paul D. Beer 《Angewandte Chemie (International ed. in English)》2014,53(44):11716-11754
Since the start of this millennium, remarkable progress in the binding and sensing of anions has been taking place, driven in part by discoveries in the use of hydrogen bonding, as well as the previously under‐exploited anion–π interactions and halogen bonding. However, anion supramolecular chemistry has developed substantially beyond anion recognition, and now encompasses a diverse range of disciplines. Dramatic advance has been made in the anion‐templated synthesis of macrocycles and interlocked molecular architectures, while the study of transmembrane anion transporters has flourished from almost nothing into a rapidly maturing field of research. The supramolecular chemistry of anions has also found real practical use in a variety of applications such as catalysis, ion extraction, and the use of anions as stimuli for responsive chemical systems. 相似文献
107.
Molecular Parameters and Transmembrane Transport Mechanism of Imidazolium‐Functionalized Binols 下载免费PDF全文
Dr. Marc Vidal Prof. Dr. Andreea Schmitzer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(32):9998-10004
We describe the molecular parameters governing the transmembrane activity of imidazolium‐functionalized anion transporters and present a detailed mechanistic study. These ionophores adopt a mobile‐carrier mechanism for short methyl and butyl chains, a combined mobile‐carrier/transmembrane‐pore mechanism for octyl and dodecyl chains, and form transmembrane aggregates for hexadecyl chains. 相似文献
108.
A Flexible Solution to Anion Transport: Powerful Anionophores Based on a Cyclohexane Scaffold 下载免费PDF全文
James A. Cooper Steven T. G. Street Prof. Anthony P. Davis 《Angewandte Chemie (International ed. in English)》2014,53(22):5609-5613
Transmembrane anion carriers (anionophores) have potential for biological activity, including the treatment of channelopathies such as cystic fibrosis. A new family of anionophores has been synthesized, in which three thiourea groups are mounted on a cyclohexane‐based scaffold. Though conceptually related to earlier polycyclic systems, these molecules are simpler and far more accessible. Preorganization is somewhat reduced compared to earlier systems, and anion affinities are correspondingly lower. However, transport activities set new records. This surprising performance suggests a role for controlled flexibility in the design of transmembrane anion carriers. 相似文献
109.
Two macrocyclic zinc(II) complexes {[ZnL(VO3)2]·0.33H2O}n(1) and [ZnL(H2O)2][Ni(CN)4](2)(L = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane) have been obtained from the reactions of [ZnL](ClO4)2 with NH4VO3 and K2[Ni(CN)4], respectively, and structurally characterized by elemental analysis, IR, XRPD, TG and X-ray diffraction. Single-crystal X-ray diffraction analyses indicated that the Zn(II) atom lies on an inversion center and is octahedrally coordinated by four nitrogen atoms of the tetradentate macrocyclic ligand in the equatorial plane and two oxygen atoms of [VO4] tetrahedra in the axial positions in 1, and two oxygen atoms of two water molecules in 2. Complex 1 shows a three-dimensional structure, which is constructed by the links of [VO3]nn- chains with [ZnL]2+, forming one-dimensional channels occupied by guest water molecules. The monomers of [ZnL(H2O)2]2+ and [Ni(CN)4]2- are connected through the intermolecular hydrogen bonds to form a two-dimensional sheet in complex 2. 相似文献
110.