Intramolecular 1,3-Dipolar Cycloadditions and Intramolecular Ene Reactions of 2-(Alkenyloxy)benzaldehyde Arylhydrazones
作者:Tomio Shimizu、Yoshiyuki Hayashi、Yoshitaka Kitora、Kazuhiro Teramura
DOI:10.1246/bcsj.55.2450
日期:1982.8
2-(3-Aryl-2-propenyloxy)benzaldehyde (or 1-naphthaldehyde) arylhydrazones undergo an intramolecular cycloaddition reaction via their 1,3-dipolar tautomers, azomethine imines, to the alkenyl group. Initial cycloadducts were converted to dehydrogenated compounds under the reaction conditions. On the other hand, introduction of cyano or ethoxycarbonyl groups instead of the aryl group into 3-position of
2-(3-Aryl-2-propenyloxy)苯甲醛(或1-萘醛)芳腙通过其1,3-偶极互变异构体偶氮甲亚胺与烯基发生分子内环加成反应。在反应条件下,初始环加合物转化为脱氢化合物。另一方面,将氰基或乙氧基羰基代替芳基引入邻丙烯氧基的3-位,分别得到3-氰甲基-4-色满酮芳基腙或相应的乙氧基羰基衍生物。这些腙的形成被解释为分子内烯反应。反应过程取决于烯基取代基的性质。