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

• 来源期刊: 中国化学(英文版)
• 年，卷（期）: 2008,（12）
• 页码范围: 2261-2266
• 页数: 6页
• 语种: 英文

摘要

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 bro-mides and activated chlorides could be recovered and reused three times without a loss of catalytic efficiency.