The first Rh-catalyzed C-H amidation of pyridines is reported. The incorporation of a substituent at the C2 position both is crucial to the success of this transformation and provides considerable scope for further elaboration of the resulting products. Among these compounds, 2-chloropyridines allow access to a selection of intermediates including a versatile azaquinazoline scaffold.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/acs.orglett.6b01612 | DOI Listing |
Inorg Chem
December 2024
Henan Key Laboratory of Polyoxometalate Chemistry, College of Chemistry and Molecular Sciences, Henan University, Kaifeng, Henan 475004, P. R. China.
Amide compounds are widely present in drug molecules and natural products, which can be synthesized by acid-amine condensation. It is urgent to design new photocatalysts for achieving both nitroaromatic reduction and C-H oxidation to obtain raw materials, carboxylic acids, and aromatic amines. Herein, a novel isopolymolybdate-incorporated photoactive metal-organic framework, -TPT, was constructed by combining the oxidation catalyst [MoO], Ni(II) cation, and photosensitive ligand 2,4,6-tri(4-pyridyl)-1,3,5-triazine (TPT).
View Article and Find Full Text PDFChem Asian J
December 2024
National Institute of Pharmaceutical Education and Research, Medicinal Chemistry, Sector 67, 160062, S. A. S. Nagar, INDIA.
Ru(II)-Catalyzed "On Water" direct aryl C(sp2)-H amidation of 2-arylbenzo[d]-thiazole/oxazole with acyl azide is reported under silver-free condition. Deuterium scrambling experiments suggested reversible C-H activation catalyzed by active cationic ruthenium species. The organic solvents such as DCE, DMF, DMSO, MeCN, dioxane, and PhMe were not conducive for the C-H amidation except for PhCl in which case, however, inferior yield (31%) was obtained.
View Article and Find Full Text PDFBeilstein J Org Chem
December 2024
Department of Chemical Science and Engineering, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501, Japan.
The C-H arylation of 2-quinolinecarboxyamide bearing a C-Br bond at the -aryl moiety is carried out with a palladium catalyst. The reaction proceeds at the C-H bond on the pyridine ring adjacent to the amide group in the presence of 10 mol % Pd(OAc) at 110 °C to afford the cyclized product in 42% yield. The yield is improved to 94% when the reaction is performed with PPh as a ligand of palladium.
View Article and Find Full Text PDFOrg Lett
December 2024
Department of Chemistry and Molecular Biology, University of Gothenburg, SE-41296 Gothenburg, Sweden.
We present a highly selective protocol for the benzylation of -aryl amides. This method offers mild conditions, excellent site specificity, and scalability, enabling the synthesis of diarylmethane amides and dibenzoazepines. The protocol allows for one-pot diagonal dibenzylation of dianilides, creating valuable precursors for pharmaceutically active compounds and addressing limitations in current direct C-H activation methodologies.
View Article and Find Full Text PDFJ Org Chem
December 2024
Department of Chemistry, 107 Physical Sciences, Oklahoma State University, Stillwater, Oklahoma 74078, United States.
Fused heterocyclic scaffolds, such as benzimidazoles or larger ring systems containing a benzimidazole fragment, are frequently encountered in pharmaceutical compounds and other biologically active molecules. While there are many examples of N9- and/or C3-substituted 9-benzo[4,5]imidazo[2,1-][1,2,4]triazoles, current examples of the regioselective preparation of N1-substituted 1-benzo[4,5]imidazo[2,1-][1,2,4]triazoles are limited to N1-aryl substituted compounds, which also contain a C3-substituent. Here, we report an iodine-promoted C-H bond amination reaction that allows the selective preparation of 1-benzo[4,5]imidazo[2,1-][1,2,4]triazoles with a variety of aryl and alkyl N1-substituents.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!