Use of Formic Acid as a CO Surrogate for the Reduction of Nitroarenes in the Presence of Dienes: A Two‐Step Synthesis of <i>N</i>‐Arylpyrroles via 1,2‐Oxazines
作者:Manar Ahmed Fouad、Francesco Ferretti、Simone Galiè、Fabio Ragaini
DOI:10.1002/ejoc.202300809
日期:2023.10.9
Formic acid was employed as a CO surrogate to deoxygenate nitroarenes to nitrosoarenes, a reaction catalyzed by a palladium/phenanthroline complex. Nitrosoarenes, trapped by conjugated dienes, afforded 3,6-dihydro-2H-[1,2]-oxazines. The latter were then transformed into N-arylpyrroles employing CuCl as the catalyst. The reaction allows to prepare pyrroles lacking any substituent in the 2 and 5 positions
使用甲酸作为 CO 替代物,将硝基芳烃脱氧为亚硝基芳烃,该反应由钯/菲咯啉络合物催化。亚硝基芳烃被共轭二烯捕获,得到 3,6-二氢-2H- [ 1,2]-恶嗪。然后使用 CuCl 作为催化剂将后者转化为N-芳基吡咯。该反应可以制备在 2 和 5 位上缺乏任何取代基的吡咯,而使用大多数吡咯合成方法很难生产这种吡咯。