Metal-free photochemical carbene-transfer reactions of tosylhydrazones were developed under blue light irradiation at room temperature. This reaction constructs C-X (X=C, N, O, S) bonds and cyclopropanes from readily available and stable starting materials.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1002/asia.202000378 | DOI Listing |
J Org Chem
January 2025
College of Chemistry and Environmental Science, Qujing Normal University, Qujing, Yunnan 655011, China.
A novel metal- and azide-free methodology for the synthesis of trifluoromethylated 1,2,3-triazoles from arylamines with a new 3-bromo-1,1,1-trifluoropropan-2-one derived tosylhydrazone has been developed under mild reaction conditions. The new α-bromo-trifluoromethylated tosylhydrazone reagent was operationally safe and bench-stable from low-cost and readily commercially available starting materials in the iodine-promoted aerobic oxidative cycloaddition reaction with arylamines, affording a variety of trifluoromethylated 1,2,3-triazoles in good to excellent yields.
View Article and Find Full Text PDFNat Commun
December 2024
Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research, Ministry of Education of China, Key Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan Province, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha, Hunan, 410081, China.
Owning to the versatile nature in participation of Diels-Alder (D-A) reactions, the development of efficient approaches to generate active ortho-quinodimethanes (o-QDMs) has gained much attention. However, a catalytic method involving coupling of two readily accessible components to construct o-QDMs is lacking. Herein, we describe a palladium carbene migratory insertion enabled dearomative C(sp)-H activation to form active o-QDM species through the cross-coupling of N-tosylhydrazones with aryl halides.
View Article and Find Full Text PDFChem Sci
November 2024
Departamento de Química Orgánica e Inorgánica, Instituto Universitario de Química Organometálica "Enrique Moles", Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Oviedo C/ Julián Clavería 8 33006 Oviedo Spain
The reactions of cyclic α,β-unsaturated -tosylhydrazones and alkylboronic acids promoted by 370-390 nm light in the presence of a base give rise to allylic boronic acids that can be trapped as the corresponding pinacolboronates by treatment with pinacol. This reaction features wide scope regarding both coupling partners and functional group tolerance, allowing for the incorporation of a variety of natural product-derived fragments. The allylic boronic acids can be also reacted in a one-pot process with aldehydes, to produce homoallylic alcohols with very high diastereoselectivity.
View Article and Find Full Text PDFOrg Biomol Chem
November 2024
College of Chemistry and Chemical Engineering, Nantong University, Nantong 226019, People's Republic of China.
A palladium-catalyzed cascade reaction of α,β-unsaturated -tosylhydrazones with iodoarene derivatives containing a nucleophilic group has been developed, which provides facile access to 2-chromenes and 2-quinolines, respectively. Additionally, the double Pd-carbene migratory insertion/nucleophilic substitution processes for the synthesis of a ternary heterocyclic skeleton were possible in the developed catalytic system.
View Article and Find Full Text PDFRSC Adv
September 2024
Department of Chemistry, Manipal University Jaipur Jaipur (Rajasthan) VPO-Dehmi-Kalan, Off Jaipur-Ajmer Express Way Jaipur Rajasthan 303007 India
An oxidative deprotection of tosylhyrdazones has been demonstrated to afford benzoic acids using iodine and DMSO system. This efficient oxidative deprotection protocol offers exceptional functional group toleration under mild reaction conditions without any initiators or bases. Notably, the tosylhydrazone with the heteroaryl ring or with the aryl ring having base-sensitive hydroxyl and ester functional groups smoothly afforded the corresponding benzoic acid analogues under developed conditions.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!