A5023415427- Organoboron and organosilicon chemistry
- Chemical Synthesis and Analysis
- Asymmetric Synthesis and Catalysis
- Synthetic Organic Chemistry Methods
- Photonic and Optical Devices
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Chemical Synthesis and Reactions
- Optical Coatings and Gratings
- Asymmetric Hydrogenation and Catalysis
- Catalytic Cross-Coupling Reactions
- Semiconductor Lasers and Optical Devices
- Advanced Synthetic Organic Chemistry
- Silicon Nanostructures and Photoluminescence
- Photonic Crystals and Applications
- Plasmonic and Surface Plasmon Research
- Catalytic C–H Functionalization Methods
- Genetics, Bioinformatics, and Biomedical Research
- Click Chemistry and Applications
- Semiconductor Quantum Structures and Devices
- Monoclonal and Polyclonal Antibodies Research
- Advanced Fiber Laser Technologies
- Photorefractive and Nonlinear Optics
- Carbohydrate Chemistry and Synthesis
- Surface Roughness and Optical Measurements
University of Alberta
2015-2024
Alberta Hospital Edmonton
2015-2020
Centennial College
2016-2020
John Wiley & Sons (United Kingdom)
2017
Hudson Institute
2017
University of Winnipeg
2016
Louisiana State University Agricultural Center
2014
Alberta Glycomics Centre
2003-2013
Eli Lilly (United States)
2011
Novartis (United States)
2009
We report the effect of metal-island size variation in nanoparticle-enhanced photodetectors. Nanoparticle was controlled by varying deposition and annealing conditions used to produce films. Increasing silver-island particles fabricated onto 165 nm thick silicon-on-insulator (SOI) photodetectors resulted a dramatic increase observed photocurrent. A nearly factor-of-20 photocurrent enhancement for light wavelength 800 nm, significant improvement over previously reported results. The is linked...
This study describes a new class of carbohydrate-binding boronic acids. ortho-Hydroxymethyl phenylboronic acid (boronophthalide) was shown to be superior the well-established dialkylamino ("Wulff-type") analogues, and it is more soluble in aqueous solvents. The most significant finding this work surprising ability ortho-hydroxyalkyl arylboronic acids complex model glycopyranosides under physiologically relevant conditions. These units appear hexopyranosides mainly using their 4,6-diol....
Taming carboxylic acids: ortho-Iodo- and ortho-bromophenylboronic acids are exceptional organocatalysts in atom-economical amidations between free amines, including functionalized ones, can also provide LUMO-lowering activation [4+2] cycloadditions of α,β-unsaturated acids. Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2002/2008/z705468_s.pdf or from author. Please note: The publisher not responsible content functionality any...
According to the amyloid cascade hypothesis, cerebral deposition of amyloid-β peptide (Aβ) is critical for Alzheimer's disease (AD) pathogenesis. Aβ generation initiated when β-secretase (BACE1) cleaves precursor protein. For more than a decade, BACE1 has been prime target designing drugs prevent or treat AD. However, development such agents turned out be extremely challenging, with major hurdles in cell penetration, oral bioavailability/metabolic clearance, and brain access. Using...
The importance of amides as a component biomolecules and synthetic products motivates the development catalytic, direct amidation methods employing free carboxylic acids amines that circumvent need for stoichiometric activation or coupling reagents. ortho-Iodophenylboronic acid 4a has recently been shown to catalyze reactions at room temperature in presence 4A molecular sieves dehydrating agent. Herein, arene core ortho-iodoarylboronic catalysts optimized with regards electronic effects ring...
Boronic ester, one typical example of dynamic covalent bonds, has presented great potential to prepare self-healing hydrogels. However, most currently reported hydrogels based on boronic esters are formed at pH > 8, which impeded their further use in physiological conditions. In this study, we designed two kinds zwitterionic copolymers with benzoxaborole and catechol pendant groups, respectively. Owing the lower pKa value (7.2), gelation can happen easily 7.4 PBS after mixing these due...
We report the degree to which resonances associated with metal island films can be used enhance sensitivity of very thin semiconductor photodetectors. The couple incident light into waveguide modes detector, resulting in increased absorption. To characterize coupling, silver-, gold-, and copper-island layers were formed on surface a thin-film photodetector fabricated 0.16 μm thick silicon layer silicon-on-insulator (SOI) wafer. copper islands gave best result, producing more than an order...
Despite the popularity of boron and silicon allylation reagents in stereocontrolled synthesis, they suffer from a number inherent limitations that have slowed down their development as synthetic tools for nucleophilic additions to carbonyl compounds imine derivatives. These are low reactivity diastereoselectivity allyl trialkylsilane reagents, lack catalytic systems activation substoichiometric control enantioselectivity reagents. To develop more efficient general methods absolute...
The Hermite–Gauss and Laguerre–Gauss modes are well-known beam solutions of the scalar Helmholtz equation in paraxial limit. As such, they describe linearly polarized fields or single Cartesian components vector fields. wave admits, limit, a family localized Bessel–Gauss that can entire transverse electric field. Two recently reported members this modes.
In contrast to normal boronic acids, o-hydroxymethyl phenylboronic acid (benzoboroxole) has the capability of complexing glycopyranosides efficiently in neutral water. The measurement association constants with a panel model hexopyranosides indicates that preferred mode binding is through cis-3,4-diol, such as found galactopyranosides, and mass spectrometric studies support 1:1 stoichiometry. complexation glucopyranosides weaker, they are bound their 4,6-diol unit. Although several factors...
We report the results of elastic light-scattering measurements random silver nanoparticle arrays fabricated onto structures supporting optical surface modes (i.e., plasmons or waveguide modes). observe dramatic, qualitative changes in resonance structure layer due to coupling with propagating modes. The effect appears arise because underlying mediate an enhanced dipole-dipole interaction between individual nanoparticles. A calculation that supports this interpretation is described.
The recent development of Lewis and Brønsted acid catalyzed manifolds for the allylboration carbonyl compounds has opened doors towards an ideal allylation methodology using stable nontoxic allylic boronates as reagents. This Account relates our laboratory's discovery acid-catalyzed allylborations, mechanistic investigations these new processes, ongoing efforts by group others a general catalytic enantioselective methodology.
Mini lectins: A new class of oligosaccharide receptors (see example) was designed by exploiting several modes molecular recognition, including the unique ability benzoboroxoles to complex hexopyranosides. The synthesis is modular, thus well suited targeting specific oligosaccharides using combinatorial libraries. important challenge carbohydrate recognition in water presents exciting opportunities chemical biology and medicine, with potential applications analysis, purification, diagnostic,...
We report a novel class of C2-symmetric chiral diols derived from the hydrobenzoin skeleton. The combination these with SnCl4 under Yamamoto's concept Lewis acid assisted Brønsted acidity (LBA catalysis) leads to high levels asymmetric induction in allylboration aldehydes by commercially available allylboronic pinacol ester 1a. corresponding homoallylic alcohol products synthetically useful aliphatic are obtained excellent yields up 98:2 er. This combined manifold is also efficient...
Well B-haved! Boronyl groups are fully compatible in the copper-catalyzed asymmetric alkylation with chiral phosphoramidites to afford acyclic α-substituted allylic boronate reagents (see scheme, CuTC=copper(I) thiophene-2-carboxylate). This represents first highly enantioselective catalytic approach these compounds, which useful synthesis. Supporting information for this article is available on WWW under http://www.wiley-vch.de/contents/jc_2002/2007/z700975_s.pdf or from author. Please...
The resonance frequency of an electric dipole placed near a conducting surface is shifted by the dipole-surface interaction. This Letter reports observation and measurement these shifts at optical frequencies for experimental system that consists metal island film spaced distance $d$ from continuous Ag film. dependence shift in on shows good agreement with predicted classical theory
The development of general and more atom-economical catalytic processes for Friedel–Crafts alkylations unactivated arenes is an important objective interest the production pharmaceuticals commodity chemicals. Ferroceniumboronic acid hexafluoroantimonate salt (1) was identified as a superior air- moisture-tolerant catalyst direct variety slightly activated neutral with stable readily available primary secondary benzylic alcohols. Compared to use classical metal-catalyzed toxic halides, this...