Article
Chemistry, Multidisciplinary
Phong K. Quach, Jesse H. Hsu, Ivan Keresztes, Brett P. Fors, Tristan H. Lambert
Summary: The ring-opening metathesis polymerization of cyclopropenes using hydrazonium initiators was investigated. The initiators, formed by condensing 2,3-diazabicyclo[2.2.2]octane and an aldehyde, polymerize cyclopropene monomers through a sequence of [3+2] cycloaddition and cycloreversion reactions. The study showed that the monomer to initiator ratio had a positive correlation with the degree of polymerization.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Maxwell G. Holl, Tristan H. Lambert
Summary: The ring-opening carbonyl-olefin metathesis of cyclobutenes can be used to synthesize a variety of aldehydes, and the bistrifluoroacetic acid salt of 2,3-diazabicyclo[2.2.2]octane is an efficient catalyst for promoting these reactions.
Article
Chemistry, Organic
Tuong Anh To, Binh Khanh Mai, Thanh Vinh Nguyen
Summary: This article reports a new Bronsted acid-catalyzed carbonyl-olefin metathesis reaction using nitromethane as a solvent, which can promote intramolecular ring-closing reactions.
Article
Chemistry, Physical
Christopher C. McAtee, Daniel J. Nasrallah, Ho Ryu, Michael R. Gatazka, Rory C. McAtee, Mu-Hyun Baik, Corinna S. Schindler
Summary: We describe a regioselective Lewis-acid-catalyzed method for the synthesis of highly functionalized cyclopentadienes incorporating diverse subunits. Insightful studies suggest that the mechanism involves Lewis-acid-catalyzed cycloadditions followed by stepwise oxetane fragmentation, resulting in the formation of functionalized cyclopentadienes. This work provides new insights into the design of catalytic carbonyl-olefin metathesis reactions.
Article
Chemistry, Physical
Tanmay Malakar, Carly S. Hanson, James J. Devery, Paul M. Zimmerman
Summary: The study utilizes computational modeling to predict interactions between carbonyl compounds and FeCl3 in solution, which are then validated through experiments. The experimental results show that under different molar ratios of carbonyl to FeCl3, distinct structures have varying effects on the spectra.
Editorial Material
Chemistry, Multidisciplinary
Leah N. N. Appelhans
Summary: Plasmonic heating by nanoparticles has been utilized to enhance various chemical reactions. Now, thermoplasmonic activation has been extended to latent ruthenium catalysts for olefin metathesis triggered by visible and infrared light.
Article
Chemistry, Multidisciplinary
Tuong Anh To, Chao Pei, Rene M. Koenigs, Thanh Vinh Nguyen
Summary: In this study, the promotion of carbonyl-olefin metathesis reactions by hydrogen-bonding-assisted Bronsted acid catalysis was investigated. The role of hexafluoroisopropanol (HFIP) solvent in assisting the pTSA Bronsted acid catalyst and the current limitations of the carbonyl-olefin metathesis reaction were revealed through experimental and computational mechanistic studies.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Adrian Sytniczuk, Mariusz Milewski, Michal Dabrowski, Karol Grela, Anna Kajetanowicz
Summary: A set of macrocyclic unsaturated musk compounds were obtained through a high-concentration RCM process, achieved by forming oligomers and then undergoing backbiting metathesis reaction. The process exhibited high selectivity and yielded pure macrocyclic musk products. The reaction conditions were user-friendly and environmentally friendly, using commercially available catalyst and bio-sourced oleic acid substrates.
Article
Chemistry, Multidisciplinary
Kosuke Ono, Satoru Onodera, Hidetoshi Kawai
Summary: A novel synthetic strategy using boroxine formation for large macrocyclic molecules has been developed. This strategy utilizes the boroxine moiety as a covalent template to produce macrocyclic compounds through reactions with alkenyl chains. This method eliminates the need for template molecules and simplifies the synthetic procedure.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Organic
Atsushi Ueda, Yui Makura, Sana Kakazu, Takuma Kato, Tomohiro Umeno, Kazuhiro Hirayama, Mitsunobu Doi, Makoto Oba, Masakazu Tanaka
Summary: In this study, a selective E-type ring-closing metathesis reaction was discovered in α-helical stapled peptides. By using chiral carbocyclic α,α-disubstituted α-amino acids, a high E-selectivity was achieved, while standard acyclic amino acids resulted in lower selectivity. The stapled octapeptide exhibited a right-handed α-helical crystal structure.
Article
Chemistry, Multidisciplinary
Jun Zhu, Rui Zhang, Guangbin Dong
Summary: A rare reversible C-C single-bond metathesis reaction catalyzed by ruthenium was reported, enabling the synthesis of biaryl compounds under redox-neutral and pH-neutral conditions. The reaction mode involves unexpected 18-electron closed-shell intermediates and is expected to inspire the development of more general C-C single-bond metathesis and orthogonal cross-coupling reactions.
Article
Chemistry, Multidisciplinary
Henrik Gulyas, Shigetaka Hayano, Adam Madarasz, Imre Papai, Mark Szabo, Agota Bucsai, Eddy Martin, Jordi Benet-Buchholz
Summary: By tuning the electron donor capacity of ligands, air-stable solid adducts of tungsten and molybdenum alkylidenes can be prepared, which can spontaneously release active catalysts in solution.
COMMUNICATIONS CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Anas Semghouli, Attila M. Remete, Lorand Kiss
Summary: Novel functionalized fused-ring β-amino lactones and lactams with multiple chiral centers were synthesized from readily available strained bicyclic β-amino acids via a stereocontrolled synthetic route. The key step involved ring-rearrangement metathesis of allyl/propargyl esters or N-allylated/N-propargylated amides of (oxa)norbornene β-amino acids. The RRM transformations were investigated using commercially available catalysts. Importantly, the procedure did not alter the configurations of the chiral centers, meaning that the starting (oxa)norbornene β-amino acids predetermined the configuration of the formed products.
Article
Chemistry, Physical
Jasnoor S. Mann, Binh Khanh Mai, Thanh Vinh Nguyen
Summary: The carbonyl-alkyne metathesis (CAM) reaction is a versatile method to access alpha,beta-unsaturated carbonyl compounds, which are important precursors and structural motifs in biologically active substances. We developed an efficient organic Lewis acid catalytic system that promotes both intramolecular and intermolecular CAM reactions. Our metal-free protocol can produce a diverse family of useful organic structures from a broad range of substrates.
Article
Polymer Science
Brad H. Jones, Chad Staiger, Jackson Powers, Jeremy A. Herman, Jessica Roman-Kustas
Summary: This study introduces a novel series of linear and crosslinked polyurethanes, along with a selective depolymerization method under mild conditions. By utilizing unique polyols and specific synthesis techniques, the polymer chain can be cleaved in a controlled manner, allowing for the development of recyclable materials with potential for further re-polymerization.
MACROMOLECULAR RAPID COMMUNICATIONS
(2021)
