Reusable and Ligand-Free Palladium-Catalyzed Suzuki-Miyaura Cross-Couplings of Aryl Halides with Arylboronic Acids in Tetra-n-butylammonium Bromide

✍ Scribed by Ye-Xiang XIE; Jian WANG; Jin-Heng LI; Yun LIANG

• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 74 KB
• Volume: 26
• Category: Article
• ISSN: 0256-7660
• DOI: 10.1002/cjoc.200890401

✦ Synopsis

Abstract

Ligand‐free and reusable palladium‐catalyzed Suzuki‐Miyaura cross‐coupling reaction performed in TBAB (tetra‐n‐butylammonium bromide) was presented. It was found that the amount of water affected these reactions. Excellent results were obtained when there was w=1% of water in TBAB. In the presence of 3 mol% of Pd(OAc)~2~ and 1.5 g of TBAB (containing w=1% of water), a number of aryl halides were coupled with arylboronic acids smoothly in moderate to excellent yields. Moreover, the Pd(OAc)~2~/TBAB system among the couplings of aryl bromides and activated chlorides could be recovered and reused three times without a loss of catalytic efficiency.