A5088036863- Photochromic and Fluorescence Chemistry
- Photoreceptor and optogenetics research
- Porphyrin and Phthalocyanine Chemistry
- Surfactants and Colloidal Systems
- Analytical Chemistry and Chromatography
- Photochemistry and Electron Transfer Studies
- Polydiacetylene-based materials and applications
- Spectroscopy and Quantum Chemical Studies
- Synthesis of Organic Compounds
- Organoboron and organosilicon chemistry
- Supramolecular Self-Assembly in Materials
- Photosynthetic Processes and Mechanisms
- Molecular Sensors and Ion Detection
- Advanced Chemical Physics Studies
- Protein Interaction Studies and Fluorescence Analysis
- Analytical chemistry methods development
- Cinema and Media Studies
- Analytical Chemistry and Sensors
- Fluorine in Organic Chemistry
- Minerals Flotation and Separation Techniques
- Electrochemical Analysis and Applications
- Coagulation and Flocculation Studies
- Enzyme-mediated dye degradation
- Synthesis and Reactions of Organic Compounds
- Chemical Synthesis and Analysis
University of Regina
2007-2020
Centre For Innovation And Development
2014-2019
University of Victoria
1997-2000
University of Vienna
1998-2000
University of California, Berkeley
1986
Lawrence Berkeley National Laboratory
1986
The structural aspects for the complexation of xanthone and fluorenone to α- as well β-cyclodextrins (CDxs) were explored by combining absorption, fluorescence, induced circular dichroism studies with theoretical calculations optimized structures ketone−CDx complexes their predicted ICD spectra. Detailed information on similarities differences these ketones CDxs was obtained. For both CDxs, are bound rim cavity, deeper penetration is observed β-CDx. In addition, a 1:2 complex involving α-CDx...
Quantum coherence is proclaimed to promote efficient energy collection by light-harvesting complexes and prototype organic photovoltaics. However, supporting spectroscopic studies are hindered the problem of distinguishing between excited state ground origin coherent spectral transients. Coherence amplitude maps, which systematically represent quantum beats observable in two-dimensional (2D) spectroscopy, currently prevalent tool for making this distinction. In article, we present maps a...
Donor-acceptor Stenhouse adducts (DASAs) are a novel class of solvatochromic photoswitches with increasing importance in photochemistry. Known for their reversibility between open triene and closed cyclized states, these push-pull molecules applicable suite light-controlled applications. Recent works have sought to understand the DASA photoswitching mechanism reactive state, as DASAs vulnerable irreversible "dark switching" polar protic solvents. Despite utility fluorescence spectroscopy...
Stereoselective binding of the 1-naphthyl-1-ethanol (1-NpOH) and 2-naphthyl-1-ethanol (2-NpOH) enantiomers with β-cyclodextrin (β-CD) was investigated by photophysical theoretical studies. The latter are based on structural calculations complexes their respective induced circular dichroism spectra. For 1-NpOH, where β-CD have a 1:1 (guest:CD) stoichiometry, mixture structures different geometries observed for each enantiomer. No stereoselectivity apparent these complexes. (R)- (S)-2-NpOH...
The ultrafast dynamics of unsubstituted spironaphthopyran (SNP) were investigated using femtosecond transient UV and visible absorption spectroscopy in three different solvents by semi-classical nuclear simulations. primary ring-opening the pyran unit was found to occur 300 fs yielding a non-planar intermediate first singlet excited state (S1). Subsequent planarisation relaxation product ground proceed through barrier crossing on S1 potential energy surface (PES) take place within 1.1 ps...
A ‘recover before destroy’ approach to minimise photoproduct build-up in solid state enables ultrafast studies of chemical reactions.
R. Scott Murphy, Y. Chen, T. Ward, H. Mitchell and C. Bohne, Chem. Commun., 1999, 2097 DOI: 10.1039/A905725K
Surface pressure–area isotherms were recorded under different irradiation conditions for single-component Langmuir films of three photochromic amphiphilic dithienylethenes. Nonirradiated these amphiphiles mechanically stable. In addition, a shift the to larger mean molecular areas was observed prepared from UV-light-irradiated Unexpectedly, significant expansion film visible-light-irradiated dithienylethene incorporating large branched alkyl chains. Upon further study, atomic force...
The integration of photochromic dithienylethenes (DTEs) with lipid vesicles as photoresponsive membrane disruptors for ion transport applications has been examined. We have synthesized three amphiphilic DTEs 1-3 that incorporate a terminally charged alkyl chain, and contain methyl or phenylethynyl substituents at the reactive carbons. Our reactivity studies suggest inclusion single chain favors photoactive antiparallel conformation DTEs, given significant improvement in cyclization quantum...
In this work, the facile preparation of alumina-based hybrid systems supporting soybean peroxidase (SBP) for biocatalytic applications was tested and resulting materials were compared with a previously examined heterogeneous biocatalyst containing SBP covalently immobilized on silica monoliths. The investigated to obtain structural information regarding their activity. amount immobilized, stability activity tested. Using adsorption NO as probe molecule, infrared fluorescence spectroscopy...
The complexation dynamics of radical cations with cyclodextrins (CD) was studied using photophysical techniques. Radical 4-vinylanisole and trans-anethole were formed within alpha- beta-CD cavities by two-photon photolysis the respective styrene precursors. Exit from alpha-CD complexes 1: 1 1:2 (guest: CD) stoichiometries 1:1 occurred lifetimes shorter than 100 ns. Most escape CD cavities, but a small portion do react when this host is present in high concentrations.
Two-dimensional spectra of a dimer were measured to determine the timescale for electronic decoherence at room temperature. Anti-correlated beats in crosspeaks observed only during period corresponding homogeneous lifetime.
Reduction of perillaldehyde by lithium in ammonia gives products the structures which depend on reaction conditions. Shisool (p-menth-8- en-7-ol) undergoes double-bond migration presence acids. The corresponding aldehyde, with dimethylsulfonium methylide, forms an oxiran is comparatively unreactive, rearrangement or reduction accompanying opening oxiran. conversion shisool into 5-(β-hydroxyethyl)-2-isopropylcyclohexanone was frustrated only partial double bond.
The seven-membered cyclic borane obtained from the reaction of linalyl acetate and thexylborane loses 2,3-dimethylbut-2-ene, resulting dialkylborane gives an alcohol on treatment with sodium cyanide, followed by trifluoroacetic anhydride oxidation. structure is confirmed synthesis. generality this was investigated but, dialkylboranes examined, only 9-borabicyclononane participated in cyanidation procedure. A simple synthesis menthone presented.
Three (bola)amphiphilic spirooxazines have been synthesized and their photochromism has characterized. The large biphotochromic structure of 2 significantly affects its conformational flexibility the rate constants for thermal ring closure are particularly dependent on lipid phase state. Two comprehensive ion permeation studies were performed to examine effect spirooxazine inclusion isomerization membrane permeability. In all cases, open-ring isomers these more disruptive in bilayer...
A synthetic route for the preparation of amphiphilic asymmetrical dithienylethenes that incorporate methyl groups at 4- and 4′-positions an aryl group one reactive carbons has been developed. The presence a bulky substituent ensures relatively large change in molecular geometry upon photoisomerization, whereas provide enhanced photostability. Notably, effect was systematically revealed en to dithienylethene precursors. In particular, this formal substitution reaction significantly inhibited...