A highly efficient and aerobic protocol for the synthesis of N-heteroaryl substituted 9-arylcarbazolyl derivatives via a palladium-catalyzed ligand-free Suzuki reaction
作者:Xiaofeng Rao、Chun Liu、Jieshan Qiu、Zilin Jin
DOI:10.1039/c2ob26119g
日期:——
A palladium-catalyzed aerobic and ligand-free Suzuki reaction in aqueous ethanol has been developed for the synthesis of N-heteroaryl substituted 9-arylcarbazolyl derivatives. A number of N-heteroaryl halides, namely 2-halogenated pyridines, 2-bromoquinoline, 5-bromopyrimidine and 2-chloropyrazine, were coupled with 4-(9H-carbazol-9-yl)phenylboronic acid (CPBA) or 9-phenyl-9H-carbazol-3-ylboronic acid
水溶液中钯催化的需氧和无配体的Suzuki反应 乙醇已开发出用于合成N-杂芳基取代的9-芳基咔唑基衍生物的化合物。许多N-杂芳基卤化物,即2-卤代吡啶,2-溴喹啉, 5-溴嘧啶 和 2-氯吡嗪,加上 4-(9 H-咔唑-9-基)苯基硼酸(CPBA)或9-苯基-9 H-咔唑-3-基硼酸(PCBA)有效地在短的反应时间内提供优良的良率。此外,Pd(OAc)2的催化体系–乙醇/高氧2-K 2 CO 3已成功地扩展到N-杂芳基卤化物与各种芳基硼酸的交叉偶联。结果表明,本方案中的交叉偶联反应被氧气促进。