The cobalt-catalyzed chelation assisted ortho C-H allylation of aromatic amides with unactivated aliphatic alkenes is reported. The reaction proceeds in air under mild reaction conditions, providing allylated products in good to excellent yields with high E-selectivities. This operationally simple method shows a high functional group tolerance.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1039/c6cc05330k | DOI Listing |
Org Lett
March 2024
School of Chemical Sciences, National Institute of Science Education and Research (NISER), Bhubaneswar, Odisha 752050, India.
Herein, we report the facile synthesis of indole C(4)-acrylophenone using a C-H bond activation strategy. For this conversion, an unsymmetrical alkyne (phenylethynyl ether) in the presence of cobalt(III)-catalyst works efficiently. In this process, alkyne gets oxidized in the presence of generated water, which is the key step for this method, for which trifluoroethanol is the water source.
View Article and Find Full Text PDFJ Am Chem Soc
February 2024
Key Laboratory of Precision and Intelligent Chemistry, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, University of Science and Technology of China, Hefei 230026, China.
Metal-hydride-catalyzed alkene hydroalkylation has been developed as an efficient method for C(sp)-C(sp) coupling with broad substrate availability and high functional group compatibility. However, auxiliary groups, a conjugated group or a chelation-directing group, are commonly required to attain high regio- and enantioselectivities. Herein, we reported a ligand-controlled cobalt-hydride-catalyzed regio-, enantio-, and diastereoselective oxyheterocyclic alkene hydroalkylation without chelation-directing groups.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
December 2023
Department of Chemistry, Princeton University, Princeton, NJ 08544, USA.
Evaluation of the relative rates of the cobalt-catalyzed C(sp )-C(sp ) Suzuki-Miyaura cross-coupling between the neopentylglycol ester of 4-fluorophenylboronic acid and N-Boc-4-bromopiperidine established that smaller N-alkyl substituents on the phenoxyimine (FI) supporting ligand accelerated the overall rate of the reaction. This trend inspired the design of optimal cobalt catalysts with phenoxyoxazoline (FOx) and phenoxythiazoline (FTz) ligands. An air-stable cobalt(II) precatalyst, (FTz)CoBr(py) was synthesized and applied to the cross-coupling of an indole-5-boronic ester nucleophile with a piperidine-4-bromide electrophile that is relevant to the synthesis of reported toll-like receptor (TLR) 7/8 antagonist molecules including afimetoran.
View Article and Find Full Text PDFACS Omega
July 2023
ZhengZhou JiShu Institute of AI Science, Zhengzhou, Henan 451162, P. R. China.
Organosilicon and organotin compounds have been widely used in many fields, such as organic synthesis, materials science, and biochemistry, because of their unique physical and electronic properties. Recently, two novel compounds containing C-Si or C-Sn bonds have been synthesized. These compounds can be used for late modification of drug-like molecules such as probenecid, duloxetine, and fluoxetine derivatives.
View Article and Find Full Text PDFJ Org Chem
July 2023
School of Pharmaceutical and Chemical Engineering, Taizhou University, Jiaojiang 318000, China.
A method for chemoselective reduction of 2-pyridyl ketones and related -heteroaryl compounds catalyzed by cobalt stearate using DMF as a hydride source is developed. The ketone substrate is activated by chelation with cobalt, which makes the present method highly chemoselective. A possible reaction mechanism is proposed on the basis of control experiments.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!