A5062873397- Advanced Polymer Synthesis and Characterization
- Photopolymerization techniques and applications
- Radical Photochemical Reactions
- Innovative Microfluidic and Catalytic Techniques Innovation
- Click Chemistry and Applications
- Axial and Atropisomeric Chirality Synthesis
- Organoboron and organosilicon chemistry
- Photochromic and Fluorescence Chemistry
- Radiopharmaceutical Chemistry and Applications
- Block Copolymer Self-Assembly
- Monoclonal and Polyclonal Antibodies Research
- Synthetic Organic Chemistry Methods
- Fullerene Chemistry and Applications
- Dental materials and restorations
- Molecular spectroscopy and chirality
- Porphyrin and Phthalocyanine Chemistry
- Magnetism in coordination complexes
- Fuel Cells and Related Materials
- Luminescence and Fluorescent Materials
- Chemical Synthesis and Analysis
- Organoselenium and organotellurium chemistry
- Pharmacological Effects and Toxicity Studies
- Boron Compounds in Chemistry
- Graphene research and applications
- Machine Learning in Materials Science
Massachusetts Institute of Technology
2023-2024
Cornell University
2016-2021
Photoinitiated cationic polymerizations are widely used in industrial processes; however, gaining photocontrol over chain growth would expand the utility of these methods and facilitate design novel complex architectures. We report herein a polymerization regulated by visible light. This proceeds under mild conditions: combination metal-free photocatalyst, chain-transfer agent, light irradiation enables synthesis various poly(vinyl ether)s with good control molecular weight dispersity as...
The ability to combine two polymerization mechanisms in a one-pot setup and switch the monomer selectivity via an external stimulus provides excellent opportunity control polymer sequence structure. We report strategy that enables incorporation be determined selection of wavelength light through selective activation either cationic or radical processes. This method synthesis varying polymeric structures under identical solution conditions but with simple modulation stimulus. Additionally,...
The mechanism of the recently reported photocontrolled cationic polymerization vinyl ethers was investigated using a variety catalysts and chain-transfer agents (CTAs) as well diverse spectroscopic electrochemical analytical techniques. Our study revealed complex activation step characterized by one-electron oxidation CTA. This is followed mesolytic cleavage resulting radical cation species, which leads to generation reactive cation-this species initiates ether monomer-and dithiocarbamate...
The development of next-generation materials is coupled with the ability to predictably and precisely synthesize polymers well-defined structures architectures. In this regard, discovery synthetic strategies that allow on demand control over monomer connectivity during polymerization would provide access complex in a modular fashion remains grand challenge polymer chemistry. Article, we report method where selectivity controlled by application two orthogonal stimuli. Specifically, developed...
Varying molecular weight distributions (MWDs) have the potential to precisely tune polymer properties, but this approach remains relatively unexplored owing a lack of synthetic methods that provide control over exact makeup distribution. Herein, we report simple and highly efficient strategy for addressing challenge through temporal regulation initiation in anionic polymerization styrene. This method yields unprecedented shape MWD facilitates synthesis diblock copolymers with controlled...
A signature of photo-mediated controlled polymerizations is the ability to modulate rate polymerization by turning light source ‘on’ and ‘off.’ However, in many reported systems, growth can be reproducibly observed during dark periods. In this study, emerging radical are evaluated with situ 1H NMR monitoring assess their behavior dark. Interestingly, it that Cu-mediated systems undergo long-lived, linear periods organic media. Please note: The publisher not responsible for content or...
Given the ubiquity of carbon-hydrogen bonds in biomolecules and polymer backbones, development a photocontrolled polymerization selectively grafting from C-H bond represents powerful strategy for conjugation. This approach would circumvent need complex synthetic pathways currently used to introduce functionality at chain end. On this basis, we developed hydrogen-atom abstraction that allows controlled hydridic using benzophenone photocatalyst, trithiocarbonate-derived disulfide, visible...
Gaining temporal control over chain growth is a key challenge in the enhancement of controlled living polymerizations. Though research on photocontrolled polymerizations still its infancy, it has already proven useful development previously inaccessible materials. Photocontrol now been extended to cationic using 2,4,6-triarylpyrylium salts as photocatalysts. Despite ability stop polymerization for short time, monomer conversion was observed long dark periods. Improved catalyst systems based...
The ability to fabricate polymeric materials with spatially controlled physical properties has been a challenge in thermoset manufacturing. To address this challenge, work takes advantage of photoswitchable polymerization that selectively incorporates different monomers at growing chain by converting from cationic radical polymerizations through modulation the wavelength irradiation. By regulating dosage and light applied system, mechanical crosslinked material can be temporally tuned....
Cationic polymerizations provide a valuable strategy for preparing macromolecules with excellent control but are inherently sensitive to impurities and commonly require rigorous reagent purification, low temperatures, strictly anhydrous reaction conditions. By using pentacarbomethoxycyclopentadiene (PCCP) as the single-component initiating organic acid, we found that diverse library of vinyl ethers can be controllably polymerized under ambient Additionally, chain-end fidelity is maintained...
The utility of antibody therapeutics is hampered by potential cross-reactivity with healthy tissue. Over the past decade, significant advances have been made in design activatable antibodies, which increase, or create altogether, therapeutic window a parent antibody. Of these, prodrugs (pro-antibodies) are masked antibodies that advanced most for use. They designed to reveal active, only when encountering proteases upregulated microenvironment targeted disease tissue, thereby minimizing...
Abstract The synthesis of high‐molecular‐weight poly(vinyl ethers) under mild conditions is a significant challenge, since cationic polymerization reactions are highly sensitive to chain‐transfer and termination events. We identified novel effective hydrogen bond donor (HBD)–organic acid pair that can facilitate controlled vinyl ethers ambient with excellent monomer compatibility. Poly(vinyl molar masses exceeding 50 kg mol −1 be produced within 1 h without elaborate reagent purification....
Abstract Während der letzten 40 Jahre erzielten Forscher bei Untersuchung photoinitiierter kationischer Polymerisationen enorme Erfolge sowohl im industriellen Bereich als auch akademischen Umfeld. Unzählige Photoinitiierungssysteme wurden entwickelt, wodurch die Polymerisation eines breiten Spektrums von Monomeren (z. B. Epoxiden, Vinylethern, Alkenen, cyclischen Ethern und Lactonen) unter praktischen, kostengünstigen umweltschonenden Bedingungen ermöglicht wurde. Aufgrund Fortschritte in...
Abstract Gaining temporal control over chain growth is a key challenge in the enhancement of controlled living polymerizations. Though research on photocontrolled polymerizations still its infancy, it has already proven useful development previously inaccessible materials. Photocontrol now been extended to cationic using 2,4,6‐triarylpyrylium salts as photocatalysts. Despite ability stop polymerization for short time, monomer conversion was observed long dark periods. Improved catalyst...
<p>Given the ubiquity of C–H bonds in biomolecules and polymer backbones, development a photocontrolled polymerization from bond would represent powerful strategy for selective conjugation precluding several synthetic steps to introduce complex functionality. We have developed hydrogen-atom abstraction that allows controlled C–H using benzophenone photocatalyst, trithiocarbonate-derived disulfide, visible light. perform variety ethers, alkanes, unactivated bonds, alcohols as well...
Abstract The synthesis of high‐molecular‐weight poly(vinyl ethers) under mild conditions is a significant challenge, since cationic polymerization reactions are highly sensitive to chain‐transfer and termination events. We identified novel effective hydrogen bond donor (HBD)–organic acid pair that can facilitate controlled vinyl ethers ambient with excellent monomer compatibility. Poly(vinyl molar masses exceeding 50 kg mol −1 be produced within 1 h without elaborate reagent purification....
Given the ubiquity of C–H bonds in biomolecules and polymer backbones, development a photocontrolled polymerization from bond would represent powerful strategy for selective conjugation precluding several synthetic steps to introduce complex functionality. We have developed hydrogen-atom abstraction that allows controlled C–H using benzophenone photocatalyst, trithiocarbonate-derived disulfide, visible light. perform variety ethers, alkanes, unactivated bonds, alcohols as well showcase...
The utility of antibody therapeutics is hampered by potential cross-reactivity with healthy tissue. Over the past decade, significant advances have been made in design activatable antibodies which increase, or create altogether, therapeutic window a parent antibody. Of these, prodrugs (pro-antibodies) are masked that advanced most for use. They designed to reveal active, only when encountering proteases upregulated microenvironment targeted disease tissue, thereby minimizing off-target...
Key words nickel catalysis - asymmetric synthesis Ullmann coupling
Key words palladium catalysis - metal-organic frameworks C–H arylation tetrathiafulvalene