A5061210890- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Crystallography and molecular interactions
- Luminescence and Fluorescent Materials
- Metal-Organic Frameworks: Synthesis and Applications
- Crystal structures of chemical compounds
- Porphyrin and Phthalocyanine Chemistry
- Covalent Organic Framework Applications
- Chemical Synthesis and Analysis
- Inorganic Fluorides and Related Compounds
- Supramolecular Self-Assembly in Materials
- Electron Spin Resonance Studies
- Radical Photochemical Reactions
- Advanced NMR Techniques and Applications
- Perovskite Materials and Applications
- Synthesis and properties of polymers
- Magnetism in coordination complexes
- Solid-state spectroscopy and crystallography
- Synthesis and Properties of Aromatic Compounds
University of South Carolina
2017-2019
Kansas State University
2012
UV-irradiation of assembled urea-tethered triphenylamine dimers affords persistent and regenerable radicals whereas the compound quickly degrades in solution.
Substituted triphenylamine (TPA) radical cations show great potential as oxidants and spin-containing units in polymer magnets. Their properties can be further tuned by supramolecular assembly. Here, we examine how the of photogenerated cations, intrinsic to TPA macrocycles, are altered upon their self-assembly into one-dimensional columns. These macrocycles consist two TPAs methylene ureas, which drive assembly porous organic materials. Advantageously, activation crystals undergo guest...
With the help of robust principles crystal engineering, it is possible to construct co-crystals where two or more different molecular entities coexist in same crystalline lattice; supramolecular assembly driven by noncovalent interactions, most commonly hydrogen bonds. We have synthesized ditopic amide based ligands (N-(4-pyridin-2-yl)isonicotinamide) and (N-(3-pyridin-2-yl)nicotinamide) systematically established their binding preferences when faced with aliphatic dicarboxylic acids an odd...
Supramolecular assembly of urea-tethered benzophenone molecules results in the formation remarkably persistent triplet radical pairs upon UV irradiation at room temperature, whereas no radicals were observed solution. The factors that lead to emergent organic are correlated with microenvironment around carbonyl, types proximal hydrogens, and rigid supramolecular network. absorption spectra linear analogues rationalized using time-dependent density functional theory calculations on crystal...
To establish how intermolecular interactions influence the supramolecular assembly of azopyridines, a total five co-crystals 3,3′ and 4,4′-azopyridine; 3,3′-azpy:succinic acid (3,3′-azpy:SA), 3,3′-azpy:adipic (3,3′-azpy:AA), 3,3′-azpy:suberic (3,3′-azpy:SuA), 3,3′-azpy:sebacic (3.3′-azpy:SeA), 4,4′-azpy:suberic (4,4′-azpy:SuA) were synthesized. In all 3,3′-azopyridine, there are infinite 1-D zig-zag tapes composed alternating 3,3′-azpy diacids held together by COOH⋯N(py) hydrogen bonds....
Herein, we examine how the combination of multiple intermolecular interactions influences supramolecular assembly dipyridinylmethyl oxalamides and tetrafluorodiiodobenzenes into distinct well-defined nanostructures. A series 6 regioisomers were selected crystallized resulting in 11 cocrystals 1 cocrystal solvate. Three halogen- hydrogen-bonded macrocycles observed, two which form large enough channels to accommodate disordered guest molecules. In another case, packing infinite chains formed...
UV-irradiation of a self-assembled benzophenone bis-urea macrocycle generates μm amounts radicals that persist for weeks under ambient conditions. High-field EPR and variable-temperature X-band studies suggest resonance stabilized radical pair through H-abstraction. These endogenous were applied as polarizing agent magic angle spinning (MAS) dynamic nuclear polarization (DNP) NMR enhancement. The field-stepped DNP enhancement profile exhibits sharp peak with maximum ϵ
Herein, we investigate co-crystallization of three linear co-formers that contain urea and pyridyl groups with regioisomers diiodotetrafluorobenzene (DITFB) to afford eleven co-crystals. The o-, m-, p- dipyridylureas vary distance geometry between the carbonyl oxygen two nitrogen acceptors, while donors consist NH activated halides in DITFB. Electrostatic potential calculations suggest o-dipyridylurea co-former presents significantly different acceptors. In comparison, acceptors m-...
Herein, we examine the photochemical formation of reactive oxygen species (ROS) by a porous benzophenone-containing bis-urea host (1) to investigate mechanism photooxidations that occur within confines its nanochannels. UV irradiation self-assembled in presence molecular generates both singlet and superoxide when suspended solution. The efficiency ROS generation is lower than benzophenone (BP), which could be beneficial for reactions carried out catalytically, as react quickly often...