Organocatalytic, Asymmetric Eliminative [4+2] Cycloaddition of Allylidene Malononitriles with Enals: Rapid Entry to Cyclohexadiene-Embedding Linear and Angular Polycycles
作者:Nicoletta Brindani、Gloria Rassu、Luca Dell'Amico、Vincenzo Zambrano、Luigi Pinna、Claudio Curti、Andrea Sartori、Lucia Battistini、Giovanni Casiraghi、Giorgio Pelosi、Daniela Greco、Franca Zanardi
DOI:10.1002/anie.201501894
日期:2015.6.15
A direct aminocatalytic synthesis has been developed for the chemo‐, regio‐, diastereo‐, and enantioselective construction of densely substituted polycyclic carbaldehydes containing fused cyclohexadiene rings. The chemistry utilizes, for the first time, remotely enolizable π‐extended allylidenemalononitriles as electron‐rich 1,3‐diene precursors in a direct eliminative [4+2] cycloaddition with both
已经开发出一种直接的氨基催化合成方法,用于化学,区域,非对映和对映选择性结构的稠合多环甲醛的稠合多环甲醛,其中环戊二烯环稠合。该化学方法首次在与芳香族和脂肪族α,β-不饱和醛同时直接消除[4 + 2]的环加成反应中,将远可烯化的π扩展的π-延伸的烯丙二腈作为富电子的1,3-二烯前体。通过接近6、6、5、6、7、6、6、6、6和6、5、6稠合的环系统以及与生物相关的类固醇样6证明了该方法的普遍性。 ,6,6,6,5‐和6,6,6,5,6‐环。提出了关键的[4 + 2]加成反应的逐步反应机理,即多米诺骨牌双乙烯基反应迈克尔/迈克尔/复古迈克尔反应级联。