Rhodium-Catalyzed C(sp2)-H Activation and [3+3] Annulation: Accessing Pyrano[3,2-c]chromene-2,5-diones as TASK-3
Xueqing Liu1,2, Shuoshuo Zheng1,2, Qionglin Ge3,2
1Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006, China.
Abstract:
Herein, an efficient Rh-catalyzed C-H activation/annulation between α,β-unsaturated amides and coumarin-derived iodonium ylides has been developed, affording novel pyrano[3,2-c]chromene-2,5-diones and analogues in high yields. Most products could be easily isolated by precipitation in ethanol, followed by simple filtration. Additionally, this protocol demonstrated the benefits of environmentally friendly conditions, air compatibility, good functional group compatibility, scale-up synthesis with low catalyst loading, and a recyclable Rh catalyst. Importantly, compounds 3m and 3w demonstrated moderate agonist activity on the TASK-3 channel, with I/I0 values of 1.7650 ± 0.1058 and 1.400 ± 0.0589, respectively.
More Related Videos
10:52Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
Published on: July 27, 2022
06:34Synthesis of Antiviral Tetrahydrocarbazole Derivatives by Photochemical and Acid-catalyzed C-H Functionalization via Intermediate Peroxides CHIPS
Published on: June 20, 2014
Related Concept Videos
Radical Reactivity: Intramolecular vs Intermolecular
Radical Substitution: Hydrogenolysis of Alkyl Halides with Tributyltin Hydride
The bonds formed in this reaction are stronger than the bonds broken, making it energetically favorable. The reaction follows a radical chain mechanism similar to radical halogenation...
Diazonium Group Substitution with Halogens and Cyanide: Sandmeyer and Schiemann Reactions
α-Bromination of Carboxylic Acids: Hell–Volhard–Zelinski Reaction
Electrophilic Addition to Alkynes: Halogenation
Halogenation is another class of electrophilic addition reactions where a halogen molecule gets added across a Ï bond. In alkynes, the presence of two Ï bonds allows for the addition of two equivalents of halogens (bromine or chlorine). The addition of the first halogen molecule forms a trans-dihaloalkene as the major product and the cis isomer as the minor product. Subsequent addition of the second equivalent yields the tetrahalide.
Pericyclic Reactions: Introduction
Pericyclic reactions can be classified into three categories: electrocyclic reactions, cycloaddition reactions, and sigmatropic rearrangements. Electrocyclic reactions and sigmatropic...
![Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-phosphinetriyltripiperidine]}palladium Under Mild Reaction Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F51444.jpg&w=3840&q=50)