Single and Consecutive Cyclization Reactions of Alkynyl Carbene Complexes and 8-Azaheptafulvenes: Direct Access to Polycyclic Pyrrole and Indole Derivatives
作者:José Barluenga、Jaime García-Rodríguez、Ángel L. Suárez-Sobrino、Miguel Tomás
DOI:10.1002/chem.200901257
日期:2009.9.7
The reactivity of alkynyl and enynyl Fischer carbene complexes towards 8‐azaheptafulvenes is examined. Alkynyl carbenes 1 a–f undergo regioselective [8+2] heterocyclization with 8‐aryl‐8‐azaheptafulvenes 2 a, b providing cycloheptapyrroles 3 and 4 with metal carbene or ester functionality at C3. Moreover, consecutive cyclization reactions are involved when enynyl carbenes are used. Thus, the cyclopenta[b]pyrrole
考察了炔基和炔基菲舍尔卡宾配合物对8-氮杂庚烯富烯的反应性。炔卡宾1 - ˚F经历区域选择性[8 + 2] heterocyclization 8 -芳基-8- azaheptafulvenes 2, b提供cycloheptapyrroles 3和4与C3金属卡宾或酯官能团。此外,当使用烯丙基卡宾时,涉及连续的环化反应。因此,环戊[ b ]吡咯骨架7通过连续的[8 + 2]环化和环戊环化反应形成。最初形成的环戊环加合物可以通过与经典的亲二烯体的狄尔斯-阿尔德反应截获,从而增加结构复杂性(化合物8和9)。更重要的是,吲哚骨架的构造具有高取代度和官能化来实现(化合物11 - 15)通过涉及[8 + 2]环化,R一锅序列 NC或CO插入,和环闭合。