Oxidative Palladium Catalysis in SNAr Reactions Leading to Heteroaryl Ethers from Pyridotriazol-1-yloxy Heterocycles with Aryl Boronic Acids

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• 作者：Sumrit Wacharasindhu ; Sujata Bardhan ; Zhao-Kui Wan ; Keiko Tabei ; Tarek S. Mansour*
• 刊名：Journal of the American Chemical Society
• 出版年：2009
• 出版时间：April 1, 2009
• 年：2009
• 卷：131
• 期：12
• 页码：4174-4175
• 全文大小：147K
• 年卷期：v.131,no.12(April 1, 2009)
• ISSN：1520-5126

文摘

The palladium-catalyzed oxidative coupling of pyrido- and benzotriazol-1-yloxyquinazolines and -thienopyrimidines with aryl boronic acids in the presence of Pd(PPh₃)₄ and Cs₂CO₃ under oxygen in DME containing 0.4−0.8% water for the preparation of heteroaryl ethers is described. These transformations of triazol-1-yloxy reagents demonstrate excellent O-chemoselective control under mild conditions and good yields. Mechanistic studies based on ¹⁸O labeling indicate that phenols as intermediates in S_NAr reactions with ethers are formed in oxidative and nonoxidative pathways.