1,3-Dipolar cycloadditions of<i>anhydro-5</i>-hydroxyoxazolium hydroxide generated from 2-piperidinecarboxylic acid. Isolation of the primary adduct and synthesis of tetrahydroindolizines
作者:Takane Uchida、Shigeharu Tsubokawa、Kiyoko Harihara、Kiyoshi Matsumoto
DOI:10.1002/jhet.5570150813
日期:1978.12
1,3-Dipolar cycloaddition reactions of anhydro-5-hydroxyoxazolium hydroxide 3 generated from 2-piperidinecarboxylic acid and acetic anhydride, with dimethyl and diethyl acetylene-dicarboxylates, dibenzoylacetylene, p-benzoquinone, and 1,4-naphthoquinone gave the corresponding tetrahydroindolizines. In the case of the reaction with p-benzoquinone, the dihydroindolizine 12 was also formed. The primary
的1,3-偶极环加成反应脱水-5- hydroxyoxazolium氢氧化物3从2-哌啶羧酸和乙酸酐产生的,用二甲基和二乙基乙炔二羧酸酯,dibenzoylacetylene,p苯醌,1,4-萘醌,得到相应的tetrahydroindolizines。在与对苯醌反应的情况下,也形成了二氢吲哚嗪12。从2与二苯甲酰基乙炔的反应中分离出主要的N-桥连的内酯中间体4。这些四氢吲哚并嗪向相应的芳族吲哚嗪的几次尝试转化是徒劳的。