A5083157884- Supramolecular Chemistry and Complexes
- Crystallography and molecular interactions
- Carbon dioxide utilization in catalysis
- Molecular Sensors and Ion Detection
- Boron Compounds in Chemistry
- Carbon Dioxide Capture Technologies
- Luminescence and Fluorescent Materials
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- CO2 Reduction Techniques and Catalysts
- Ionic liquids properties and applications
- Mass Spectrometry Techniques and Applications
- Analytical Chemistry and Chromatography
- Advanced NMR Techniques and Applications
- Radioactive element chemistry and processing
- Membrane Separation and Gas Transport
- Advanced Chemical Physics Studies
- Covalent Organic Framework Applications
- Organoboron and organosilicon chemistry
- Supramolecular Self-Assembly in Materials
- Phase Equilibria and Thermodynamics
- Metal-Organic Frameworks: Synthesis and Applications
- Analytical chemistry methods development
- Surface Chemistry and Catalysis
- Surfactants and Colloidal Systems
Al-Balqa Applied University
2018-2025
Constructor University
2014-2023
University of Bremen
2014-2019
Yarmouk University
2010
Hashemite University
2009-2010
Abstract Cucurbit[ n ]urils (CB ) bind guest molecules through a combination of electrostatic interactions with the carbonyl rims and hydrophobic inner cavity. Investigations solvatochromic probes in CB7 reveal that polarity cavity resembles alcohols (e.g., ‐octanol), while its polarizability ( P =0.12) apparent refractive index D =1.10±0.12) are extremely low, close to gas phase. The calculated molecular quadrupole moments CBs large (Θ zz =−120 −340 Buckingham). A survey reported binding...
Abstract Dodecaborate anions of the type B 12 X 2− and 11 Y (X=H, Cl, Br, I Y=OH, SH, NH 3 + , NR ) form strong (K a up to 10 6 L mol −1 for Br inclusion complexes with γ‐cyclodextrin (γ‐CD). The micromolar affinities reached are highest known this native CD. complexation exhibits highly negative enthalpies (up −25 kcal entropies (TΔS −18.4 both ), which position these guests at bottom end well‐known enthalpy‐entropy correlation CDs. high driving force can be traced back chaotropic effect,...
Abstract The membrane translocation of hydrophilic substances constitutes a challenge for their application as therapeutic compounds and labelling probes 1–4 . To remedy this, charged amphiphilic molecules have been classically used carriers 3,5 However, such may cause aggregation non-specific lysis 6,7 Here we show that globular dodecaborate clusters, prominently B 12 Br 2− , can function anionic inorganic broad range cargo (with molecular mass 146–4,500 Da). We cationic neutral peptides,...
Cucurbit[n]urils (CBn, n = 7, 8) serve as artificial receptors for steroids (21 tested), including the hormones testosterone and estradiol well steroidal drugs. Fluorescence displacement titrations isothermal titration calorimetry (ITC) provided up to nanomolar binding affinities in aqueous solution these hydrophobic target molecules, exceeding values of known synthetic receptors. Remarkable selectivities, even homologous steroid pairs, were investigated detail by NMR, X-ray crystal...
The synthetic macrocycle cucurbit[6]uril forms host-guest inclusion complexes with molecular dibromine and diiodine. As evidenced by their crystal structures, the encapsulated dihalogens adapt a tilted axial geometry are held in place two different types of halogen-bonding interactions, one water molecule (bond distances 2.83 Å for O···Br 3.10 O···I) other ureido carbonyl groups container itself 3.33 3.49 O···I). While former is conventional type, involving lone electron pair an oxygen...
The host-guest chemistry of large-ring cyclodextrins (LRCDs) has been largely unexplored due to the lack suitable guest molecules that bind with significant affinities enable potential applications. Herein, we report their complexation dodecaborate anions (B12X12(2-)), a novel class molecules. binding constants inorganic guests (10(4)-10(6) M(-1)) allow classification as first tight binders for LRCDs.
Metallacarboranes are a class of inorganic boron clusters that have recently been recognized as biologically active compounds. Herein, we report on the host–guest complexation several cobalt bis(1,2-dicarbollide) anions (COSANs) with cyclodextrins (CDs) in aqueous solution. The binding affinities reach micromolar values, which among highest known values for native CDs, and exceed those neutral hydrophobic organic guest molecules. entrapment COSANs inside cavity CDs was confirmed using NMR...
The synthesis and characterization of palladium(II) complexes featuring β‐ketoiminato ligands type [Pd(ArNacac)2] (4) with Ar = 2‐chlorolphenyl (a); 3‐chlorophenyl (b); 4‐chlorophenyl (c); 2,3‐dichlorophenyl (d); 2,4‐dichlorophenyl (e); 2,6‐dichlorophenyl (f); 3,5‐dichlorophenyl (g); 2,4,5‐trichlorophenyl (h); 2,4,6‐trichlorophenyl (i) is reported. molecular structure 4a‐f, h 4i in the solid state was confirmed by single‐crystal X‐ray diffraction studies. All eight crystal structures are...
The host–guest complexation of hydrocarbons (22 guest molecules) with cucurbit[7]uril was investigated in aqueous solution using the indicator displacement strategy. binding constants (103–109 M–1) increased size, pointing to hydrophobic effect and dispersion interactions as driving forces. measured affinities provide unique benchmark data for neutral molecules. Consequently, a computational blind challenge, HYDROPHOBE conducted allow comparison state-of-the-art methods predicting affinity...
In aqueous solution, host-guest complexation is frequently driven by the hydrophobic effect, which also constitutes a popular approach in design of supramolecular assemblies. Herein, we report an orthogonal assembly motif, chaotropic exploits tendency anions to associate with surfaces.
A new type of water-soluble anchor dyes, that is, dyes which carry an auxiliary unit for strong binding to macrocyclic host molecules, has been synthesized. It consists 7-nitrobenzofurazan (NBD) as a dye and the dodecaborate cluster (B12H11R) dianionic, globular, purely inorganic anchoring group cyclodextrins (Ka > 10(5) M(-1)). The synthesized dodecaborate-substituted show marked changes in their photophysical properties (UV-vis fluorescence) upon complexation with (β-CD γ-CD), such...
In contrast to Diels–Alder reactions involving heteroatom-containing substrates, the endo dimerization of cyclopentadiene responds only very weakly changes in microenvironment or presence potential catalysts (less than a factor 10 variations). This pure hydrocarbon reaction has been used as an early model predict maximum possible catalytic effect (kcat/kuncat ca. 106 M) due entropic contributions transition-state confinement [Page, M. I.; Proc. Natl. Acad. Sci. U.S.A. 1971, 68, 1678−1683]....
Abstract Dodecaborate anions of the type B 12 X 2− and 11 Y (X=H, Cl, Br, I Y=OH, SH, NH 3 + , NR ) form strong (K a up to 10 6 L mol −1 for Br inclusion complexes with γ‐cyclodextrin (γ‐CD). The micromolar affinities reached are highest known this native CD. complexation exhibits highly negative enthalpies (up −25 kcal entropies (TΔS −18.4 both ), which position these guests at bottom end well‐known enthalpy‐entropy correlation CDs. high driving force can be traced back chaotropic effect,...
Abstract The host-guest interactions of a third-generation fluoroquinone, danofloxacin (DOFL), with the macrocyclic host cucurbit[7]uril (CB7) have been investigated at different pH values (~3.5, 7.5, and 10). photophysical properties positively affected, that is, fluorescence yield lifetime increased, as well photostability DOFL improved in presence CB7. antibacterial activity is enhanced CB7, tested against four pathogenic bacteria; highest has found towards B . cereus E coli , lower S...
The rational control of forming and stabilizing reaction intermediates to guide specific pathways remains be a major challenge in electrocatalysis. In this work, we report surface active-site engineering approach for modulating electrocatalytic CO2 reduction using the macrocycle cucurbit[6]uril (CB[6]). A pristine gold functionalized with CB[6] nanocavities was studied as hybrid organic–inorganic model system that utilizes host–guest chemistry influence heterogeneous reaction. combination...
The driving forces of association between three different families macrocycles as hosts, namely cyclodextrins (α-, β-, and γ-), p-sulfonatocalix[n]arenes (n = 4–6) well cucurbit[n]urils 6–8), bicyclic azoalkane homologues guests, 2,3-diazabicyclo[2.2.1]hept-2-ene (DBH), 2,3-diazabicyclo[2.2.2]oct-2-ene (DBO) 2,3-diazabicyclo[2.2.3]non-2-ene (DBN), were examined by means calorimetric titrations, NMR spectroscopy molecular dynamics simulation, all in aqueous solution. small, spherical...
We report the formation of strong inclusion complexes between macrocyclic host cucurbit[7]uril (CB7) and more than 20 perfluorinated compounds (PFCs) in aqueous solution. The binding constants structures were determined through a combination dye displacement titrations, 19F as well 1H NMR spectroscopy, quantum chemical calculations. high affinities, for example 1.2 × 107 M− 1 perfluorohexane 1.1 108 perfluoro(methylcylohexane), are driven, among others, by low polarisability cucurbituril...
Abstract The intriguing dual‐emission behavior of p ‐ dimethylaminobenzonitrile (DMABN) and the identity associated excited states is, arguably, most extensively investigated also controversially discussed molecule‐ specific phenomenon modern photochemistry. We have now found a new, third fluorescence band when DMABN is encapsulated within water‐soluble molecular container cucurbit[8]uril (CB8). It centered between previously observed emissions assigned to elusive excimer emission from...
Undecahydro-mercapto-<italic>closo</italic>-dodecaborate (<bold>BSH</bold>), a purely inorganic cluster anion, serves as an unconventional stabilizing ligand for the preparation of gold nanoparticles (AuNPs).
A novel oligochitosan/DMSO system as a green sorbent for CO<sub>2</sub>capturing.