Electrophilic activation of secondary amides with trifluoromethanesulfonic anhydride in the presence of 2-fluoropyridine followed by introduction of a pyridine N-oxide derivative and warming affords the corresponding N-pyridinyl tertiary amide derivatives. A mechanism supported by in situ monitoring and deuterium labeling experiments is discussed.
the conversion of ketoximes and pyridine-N-oxides into 2-amidopyridines through sequential Beckmann rearrangement followed by [2,3]-sigmatropic rearrangement. The readily available ketoximes could be activated to nitrilium ions in PIII/PV redox catalysis and could efficiently participate in the domino reaction of pyridine-N-oxides, thus providing various substituted 2-amidopyridines in moderate to excellent
报道了一种有机磷催化合成取代2-氨基吡啶的方法。该方法采用小环有机磷基催化剂和氢硅烷还原剂,通过顺序贝克曼重排和[2,3]-σ重排驱动酮肟和吡啶-N-氧化物转化为2-酰胺吡啶。容易获得的酮肟可以在P III / P V氧化还原催化中被活化为腈离子,并且可以有效地参与吡啶-N-氧化物的多米诺反应,从而以中等至优异的收率提供各种取代的2-酰胺吡啶。该策略具有出色的官能团耐受性和广泛的底物范围。
Direct Dehydrative <i>N</i>-Pyridinylation of Amides
作者:Jonathan William Medley、Mohammad Movassaghi
DOI:10.1021/jo802355d
日期:2009.2.6
Electrophilic activation of secondary amides with trifluoromethanesulfonic anhydride in the presence of 2-fluoropyridine followed by introduction of a pyridine N-oxide derivative and warming affords the corresponding N-pyridinyl tertiary amide derivatives. A mechanism supported by in situ monitoring and deuterium labeling experiments is discussed.