Chelation-Mediated Palladium(II)-Catalyzed Domino Heck−Mizoroki/Suzuki−Miyaura Reactions Using Arylboronic Acids: Increasing Scope and Mechanistic Understanding

Autor: Alejandro Trejos, Samir Yahiaoui, Mats Larhed, Ashkan Fardost
Rok vydání: 2011
Předmět:
Zdroj: The Journal of Organic Chemistry. 76:2433-2438
ISSN: 1520-6904
0022-3263
DOI: 10.1021/jo1018188
Popis: A palladium(II)-catalyzed Heck-Mizoroki/Suzuki-Miyaura domino reaction involving metal coordinating dimethylaminoethyl vinyl ethers and a number of electron-rich and electron-deficient arylboronic acids has been developed. Through variation of the temperature and the concentration of the p-benzoquinone (p-Bq) ligand/reoxidant, conditions for the robust and convenient one-pot generation of diarylated-saturated ethers were identified. With the aid of coordination of the dimethylamino group to the arylpalladium intermediate, the otherwise predominant formation of the β-arylated olefin could be reversed. A reaction route involving a chelation-controlled carbopalladation, providing a p-Bq stabilized six-membered palladacycle, followed by transmetalation and reductive elimination is suggested to explain the selective formation of saturated diarylated ether products.
Databáze: OpenAIRE