Catalytic Arylation Reactions by CH Bond Activation with Aryl Tosylates

✍ Scribed by Lutz Ackermann; Andreas Althammer; Robert Born

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 145 KB
• Volume: 45
• Category: Article
• ISSN: 0044-8249
• DOI: 10.1002/anie.200504450

✦ Synopsis

Transition-metal-catalyzed cross-coupling reactions of organometallic reagents with aryl iodides, bromides, and triflates as electrophiles are reliable tools for the regioselective syntheses of compounds with CA C H T U N G T R E N N U N G (sp 2 )-CA C H T U N G T R E N N U N G (sp 2 ) linkages. [1,2] The organometallic compounds are often not commercially available or are expensive, and give rise to the formation of undesired byproducts. The direct arylation of organic compounds by CÀ H bond functionalization offers an attractive alternative. [3][4][5][6] For traditional cross-coupling reactions of organometallic species the development of electron-rich stabilizing ligands allowed the use of readily available aryl chlorides as electrophiles. [7] Contrarily, generally applicable methods for regioselective direct arylation reactions employing aryl chlorides were reported only recently. Intramolecular direct arylation reactions with aryl chlorides were reported by the groups of Bedford, [8] Buchwald, [9] Fagnou, [10,11] and others [12] to proceed in the presence of palladium complexes derived from electron-rich tertiary phosphines, such as PA C H T U N G T R E N N U N G (tBu) 3 , or 2-(di-[