Synthesis of 3,6-Dihydro-2<i>H</i>-[1, 2]-Oxazines from Nitroarenes and Conjugated Dienes, Catalyzed by Palladium/Phenanthroline Complexes and Employing Phenyl Formate as a CO Surrogate
作者:Mohamed A. EL-Atawy、Dario Formenti、Francesco Ferretti、Fabio Ragaini
DOI:10.1002/cctc.201801223
日期:2018.10.23
Palladium/phenanthroline catalyzed reduction of nitroarenes by in situ‐generated carbon monoxide, from the decomposition of phenyl formate, affords the corresponding nitrosoarenes. The latter are trapped by conjugated dienes to give the corresponding 3,6‐dihydro‐2H‐[1, 2]‐oxazines (hetero Diels‐Alder adducts). Many functional groups are well tolerated. Yields are higher than those obtainable by any
钯/菲咯啉通过原位生成的一氧化碳,从甲酸苯基酯的分解中催化还原硝基芳烃,得到相应的亚硝基芳烃。后者被共轭二烯捕获,得到相应的3,6-dihydro-2 H- [1,2]-恶嗪(杂Diels-Alder加合物)。许多功能组的耐受性良好。产率高于通过任何先前报道的方法可获得的产率,包括二烯与纯亚硝基芳烃的直接反应。该反应可在单个标准玻璃压力管中进行,而无需高压釜或高压CO管线。