Fused Heterocycles. IV. Synthesis of 7-(<i>o</i>-Hydroxyphenyl)-3,5-dimethyl-7,8-dihydro-6<i>H</i>-isoxazolo[4,5-<i>b</i>]azepines
作者:Kooturu Malla Reddi、Citineni Janakirama Rao、Ananthula Krishna Murthy
DOI:10.1246/bcsj.54.3617
日期:1981.11
Michael addition of acetylacetone to 3-methyl-4-nitro-5-(o-hydroxystyryl)isoxazoles gives 4-(o-acetoxyphenyl)-5-(3-methyl-4-nitro-5-isoxazolyl)-2-pentanones (4). Reductive cyclization of 4 with tin(II) chloride and concentrated hydrochloric acid leads to 7-(o-hydroxyphenyl)-3,5-dimethyl-7,8-dihydro-6H-isoxazolo[4,5-b]azepines. The formation of 4 has been rationalized through ortho effect. NMR and mass spectra of products have been discussed.
乙酰丙酮与3-甲基-4-硝基-5-(邻羟基苯乙烯基)异恶唑进行迈克尔加成,得到4-(邻乙酰氧基苯基)-5-(3-甲基-4-硝基-5-异恶唑基)-2-戊酮( 4)。 4 用氯化锡(II)和浓盐酸进行还原环化,得到 7-(邻羟基苯基)-3,5-二甲基-7,8-二氢-6H-异恶唑并[4,5-b]氮杂卓。 4的形成已通过邻位效应合理化。讨论了产物的核磁共振和质谱。