Thiourea -oxides are labile compounds that suffer from a quick overoxidation when directly prepared from thioureas. Therefore, we have developed an alternative route on the basis of the SO transfer from a thiirane -oxide onto sterically encumbered -heterocyclic carbenes, including imidazole- and imidazoline-ylidenes, and a cyclic alkyl amino carbene. Reaction conditions and DFT computations suggest a concerted SO transfer mechanism. Thiourea -oxides are nucleophiles adding to dimethyl acetylenedicarboxylate under fission of the S-O bond.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/acs.orglett.4c02253 | DOI Listing |
An ongoing challenge in polymer chemistry is accessing diverse block copolymers from multiple polymerization mechanisms and monomer classes. One strategy to accomplish this goal without intermediate compatibilization steps is the use of universal mediators. Thiocarbonyl thio (TCT) functional groups are well-known mediators to combine radical with either cationic or anionic polymerization, but a sequential cationic-anionic universal mediator system has never been reported.
View Article and Find Full Text PDFOrg Lett
July 2024
Institut für Organische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany.
Thiourea -oxides are labile compounds that suffer from a quick overoxidation when directly prepared from thioureas. Therefore, we have developed an alternative route on the basis of the SO transfer from a thiirane -oxide onto sterically encumbered -heterocyclic carbenes, including imidazole- and imidazoline-ylidenes, and a cyclic alkyl amino carbene. Reaction conditions and DFT computations suggest a concerted SO transfer mechanism.
View Article and Find Full Text PDFChemosphere
November 2023
Department of Environmental Science and Engineering, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing, 100029, China.
CuFeS is regarded as a promising catalyst for heterogeneous activation to remove organic contaminants in wastewater. However, effects of solvents in regulating material synthesis and catalytic activity are still not clear. Herein, we reported the role of water, ethanol, ethylene glycol (EG), glycerol, and polyethylene glycol 200 on the synthesis of CuFeS micro-flowers and their performance in activating persulfate (PS) to remove imidacloprid (IMI) pesticide.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
December 2022
Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, PA 19104, USA.
Decarbonylation along with P-atom transfer from the phosphaethynolate anion, PCO , to the Nb complex [(PNP)NbCl (N BuAr)] (1) (PNP=N[2-P Pr -4-methylphenyl] ; Ar=3,5-Me C H ) results in its coupling with one of the phosphine arms of the pincer ligand to produce a phosphanylidene phosphorane complex [(PNPP)NbCl(N BuAr)] (2). Reduction of 2 with CoCp* cleaves the P-P bond to form the first neutral and terminal phosphido complex of a group 5 transition metal, namely, [(PNP)Nb≡P(N BuAr)] (3). Theoretical studies have been used to understand both the coupling of the P-atom and the reductive cleavage of the P-P bond.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
October 2021
Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056, Basel, Switzerland.
Overcrowded alkenes are expeditiously prepared by the versatile Barton-Kellogg olefination and have remarkable applications as functional molecules owing to their unique stereochemical features. The induced stereodynamics thereby enable the controlled motion of molecular switches and motors, while the high configurational stability prevents undesired isomeric scrambling. Bistricyclic aromatic enes are prototypical overcrowded alkenes with outstanding stereochemical properties, but their stereocontrolled preparation was thus far only feasible in stereospecific reactions and with chiral auxiliaries.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!