Palladium-catalyzed asymmetric alkylation in the synthesis of cyclopentanoid and cycloheptanoid core structures bearing all-carbon quaternary stereocenters
作者:Allen Y. Hong、Nathan B. Bennett、Michael R. Krout、Thomas Jensen、Andrew M. Harned、Brian M. Stoltz
DOI:10.1016/j.tet.2011.10.031
日期:2011.12
reagents enabled divergent access to γ-quaternary acylcyclopentenes through a ring contraction pathway or γ-quaternary cycloheptenones through a carbonyl transposition pathway. Synthetic applications of these compounds were explored through the preparation of mono-, bi-, and tricyclic derivatives that can serve as valuable intermediates for the total synthesis of complex natural products. This work complements
已经开发了嵌入多种天然产物中的环戊烷和环庚烷核心结构的通用催化不对称路线。我们不同策略中的中心立体选择性转化是七元β-酮酯的对映选择性脱羧烷基化形成α-季插烯酯。认识到添加氢化物或有机金属试剂所产生的 β-羟基酮的异常反应性,使得能够通过环收缩途径获得 γ-季酰基环戊烯或通过羰基转座途径获得 γ-季环庚烯酮。通过制备单环、双环和三环衍生物探索了这些化合物的合成应用,这些衍生物可以作为复杂天然产物全合成的有价值的中间体。这项工作补充了我们之前在环己烷系统方面的工作。