substituents in the ring are suggested. The first method is based on cycloaddition of 2,5-dimethoxycarbonyl-3,4-diphenylcyclopentadienone with substituted cyclopropenes and allows cycloheptatrienes containing two or three electron-withdrawing substituents in the molecule to be obtained. The second method employs a cascade reaction between a substituted cyclopentadienone and appropriate vinyldiazoacetates
提出了两种合成环中具有各种取代基的七取代
环庚三烯的方案。第一种方法基于 2,5-二甲氧基羰基-3,4-二苯基
环戊二烯酮与取代环
丙烯的环加成反应,并允许获得分子中含有两个或三个吸电子取代基的
环庚三烯。第二种方法采用取代的
环戊二烯酮和合适的重氮
乙酸乙烯酯之间的级联反应。它允许吸电子取代基的数量增加到五个。在所有情况下,七取代的
环庚三烯仅作为可能的异构体之一形成。