Excursion to the World of Heptacyclic Compounds Made of Azulenes and Acetylenedicarboxylates
作者:Yi Chen、Erja Lehto、Peter Uebelhart、Anthony Linden、Hans-Jürgen Hansen
DOI:10.1002/hlca.201500082
日期:2015.7
Azulenes and acetylenedicarboxylates react under acid catalysis (Brønsted or Lewis) and form (2aRS,8aSR)‐2a,8a‐dihydrocyclopenta[cd]azulene‐1,2‐dicarboxylates as intermediate products, which then dimerize by central bond‐formation between C(2a1) and C(2′a1) and various peripheral C,C′‐atoms of the dihydroazulene fragments, depending on the substituents present. The reactions are often accompanied by
Azulenes和炔二羧酸酯在酸催化下(Brønsted或Lewis)反应并形成(2a RS,8a SR)-2a,8a-dihydrocyclopenta [ cd ] azulene-1,2-二羧酸酯作为中间产物,然后通过中心键之间的二聚作用而二聚C(2a 1)和C(2'a 1)以及二氢氮杂烯片段的各种外围C,C'-原子,具体取决于存在的取代基。这些反应通常伴随有副产物的形成,例如2-(azulen-1-基)富马酸酯和马来酸酯,以及其他由主要中间体的H-移位引起的副产物。两个四氢环戊并[之间H-位移CD还发现了七环结构的] azulene部分。