Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, USA.
J Am Chem Soc. 2010 Aug 18;132(32):11179-82. doi: 10.1021/ja103551x.
Structurally complex and physiologically active natural products often include bicyclic and polycyclic ring systems having defined relative and absolute configuration. Approaches that allow the construction of more than one carbocyclic ring at a time have proven valuable, in particular those that allow at the same time the control of an array of new stereogenic centers. One of the most general and most widely used protocols has been the intramolecular Diels-Alder [4 + 2] cycloaddition, in which a single stereogenic center between the diene and the dienophile can control the relative and absolute configuration of the product. We report a two-step [1 + 4 + 1] procedure for bicyclic and polycyclic construction, based on the cyclization of an omega-dienyl ketone. This is complementary to, and will likely be as useful as, the intramolecular Diels-Alder cycloaddition.
结构复杂且生理活性的天然产物通常包含具有确定的相对和绝对构型的双环和多环环系统。已证明，能够一次构建多个碳环的方法非常有价值，特别是那些能够同时控制一系列新的手性中心的方法。其中最通用和最广泛使用的方案之一是分子内 Diels-Alder [4 + 2] 环加成，其中二烯和双烯之间的单个手性中心可以控制产物的相对和绝对构型。我们报告了一种基于ω-二烯基酮环化的两步 [1 + 4 + 1] 方法，用于双环和多环构建。这与分子内 Diels-Alder 环加成互补，并且可能同样有用。
