Novel role of carbon dioxide as a selective agent in palladium-catalyzed cyclotrimerization of alkynes

✍ Scribed by Jin-Heng Li; Ye-Xiang Xie

• Publisher: John Wiley and Sons
• Year: 2010
• Tongue: English
• Weight: 328 KB
• Volume: 22
• Category: Article
• ISSN: 0256-7660
• DOI: 10.1002/cjoc.20040221209

✦ Synopsis

Abstract

Carbon dioxide was found as a selective agent to promote the palladium‐catalyzed cyclotrimerization of alkynes in water. Both aryl and alkylacetylenes afforded the corresponding cyclotrimerization products regioselectively in high yields using PdCl~2~, CuCl~2~, and CO~2~ as the catalytic system. However, tert‐butylacetylene bearing a bulky group gave a dimerization product. Mechanism of this reaction was also discussed.