From Pyridine-N-oxides to 2-Functionalized Pyridines through Pyridyl Phosphonium Salts: An Umpolung Strategy
From Pyridine-N-oxides to 2-Functionalized Pyridines through Pyridyl Phosphonium Salts: An Umpolung Strategy
复制标题
DOI：
10.1021/acs.orglett.1c02165
复制
发表时间：
2021-07-16
期刊：
影响因子：
5.2
通讯作者：
Karchava, Alexander, V
中科院分区：
文献类型：
--
作者：
Bugaenko, Dmitry, I;Yurovskaya, Marina A.;Karchava, Alexander, V
吡啶-N-氧化物与Ph 3 P在所开发的条件下的反应提供了一种前所未有的路线（吡啶-2-基）鏻盐。在用DABCO活化后，这些盐容易用作官能化的2-吡啶基亲核试剂等价物。这种umpolung策略允许亲电试剂选择性地对吡啶环进行C2官能化，避免了不稳定的有机金属试剂的产生和使用。该方案在环境温度下操作，并耐受敏感的官能团，从而能够合成具有挑战性的化合物。
The reactions of pyridine-N-oxides with Ph3P under the developed conditions provide an unprecedented route to (pyridine-2-yl)phosphonium salts. Upon activation with DABCO, these salts readily serve as functionalized 2-pyridyl nucleophile equivalents. This umpolung strategy allows for the selective C2 functionalization of the pyridine ring with electrophiles, avoiding the generation and use of unstable organometallic reagents. The protocol operates at ambient temperature and tolerates sensitive functional groups, enabling the synthesis of otherwise challenging compounds.