Generation of nitroalkanes, hydroximoyl halides and nitrile oxides from the reactions of β-nitrostyrenes with Grignard or organolithium reagents
作者:Ching-Fa Yao、Kuo-Hsi Kao、Ju-Tsung Liu、Cheng-Ming Chu、Yeh Wang、Wen-Chang Chen、Yu-Mei Lin、Wen-Wei Lin、Ming-Chung Yan、Jing-Yuan Liu、Ming-Ching Chuang、Jin-Lien Shiue
DOI:10.1016/s0040-4020(97)10356-8
日期:1998.1
products 6 and/or 7 are observed if the nitronates, generated from the substrate 1a, are added to 85% aqueous H2SO4 but only the hydrolyzed carboxylic acids 9 are generated when the β-nitrostyrenes 2 are reacted with Grignard reagents and worked up under the same condition. The nitrile oxides 7 can undergo 1,3-dipolar cycloaddition with alkenes or alkynes to generate 2-isoxazolines or isoxazoles. A one-pot
β型硝基苯乙烯1或2与格氏或有机锂试剂反应在乙醚或THF溶液由1,4-加成中间nitronates以产生甲。当用稀盐酸处理A时,获得高产率的硝基烷3(和肟4)或5。当将中间体A缓慢加入到冰冷的浓氢卤酸中时,可以分离出羟甲酰卤6、8或一氧化氮7。如果从基材1a产生的硝酸盐观察到相同的产物6和/或7。将β-硝基苯乙烯2加入到85%的H 2 SO 4水溶液中,但是当β-硝基苯乙烯2与格氏试剂反应并在相同条件下进行后处理时,仅产生水解的羧酸9。腈氧化物7可与烯烃或炔烃进行1,3-偶极环加成反应以生成2-异恶唑啉或异恶唑。据报道,通过分子内一氧化氮-烯烃环加成反应可以一锅合成[n,3,0]双环(n = 3或4)化合物23-27。