Palladium-Catalyzed Sonogashira Coupling Reaction of 2-Amino-3-Bromopyridines with Terminal Alkynes

• 作者: Dingqiao Yang Guo Cheng Lichun Liao Qing Zhu Wen Yang Yingying Deng
• 来源期刊: 催化剂现代研究(英文)
• 学科: 化学
• 关键词: Palladium Catalyst 2-Amino-3-Bromopyridines Terminal Alkynes Sonogashira Coupling Reaction
• 年，卷（期）: 2017,（3）
• 页码范围: 121-133
• 页数: 13页
• 分类号: O6

摘要

Palladium-catalyzed the Sonogashira coupling reaction of 3-halogen-2-aminopyridines 1 with terminal alkynes 2 afforded the corresponding 21 target products 3a-3u in the presence of palladium catalyst. The structure of target products 3a-3u was confirmed and characterized by 1H NMR, 13C NMR, and HRMS. The influences of different kinds of catalyst loading, bases, substrates and temperature were also investigated. Under the optimized conditions, including 2.5 mol% Pd?(CF3COO)2, 5 mol% PPh3 and 5 mol% CuI as additive, 1 mL Et3N, substrate 1 with terminal alkynes 2 for the cross-coupling reactions at 100°C for 3 h in DMF afforded the corresponding products of 2-amino-3-alkynylpyridines 3 in moderate to excellent yields (72%?-?96%). The present methodology has provided an effective synthetic method including operational convenience, high efficiency and wide-application.