Department of Chemistry , University of California , Berkeley , California 94720 , United States.
Department of Chemistry , University of California , Davis , California 95616 , United States.
J Am Chem Soc. 2018 Jul 25;140(29):9291-9298. doi: 10.1021/jacs.8b05804. Epub 2018 Jul 13.
An acid-catalyzed Prins/semipinacol rearrangement cascade reaction of hydroxylated pinene derivatives that leads to tricyclic fenchone-type scaffolds in very high yields and diastereoselectivity has been developed. Quantum chemical analysis of the selectivity-determining step provides support for the existence of an extremely flat potential energy surface around the transition state structure. This transition state structure appears to be ambimodal, i.e., the fenchone-type tricyclic scaffolds are formed in preference to the competing formation of a bornyl (camphor-type) skeleton under dynamic control via a post-transition state bifurcation (PTSB).
发展了一种酸催化的 Prins/半频哪醇重排级联反应，用于羟化蒎烯衍生物，以非常高的产率和非对映选择性得到三环型葑酮骨架。对决定选择性步骤的量子化学分析为过渡态结构周围存在极其平坦的势能面提供了支持。这种过渡态结构似乎是双重模态的，即通过后过渡态分叉（PTSB），在动态控制下，优先形成葑酮型三环骨架，而不是竞争形成莰基（樟脑型）骨架。
