Surveying approaches to the formation of carbon–carbon bonds between a pyran and an adjacent ring
作者:Jeffrey D. Frein、Tomislav Rovis
DOI:10.1016/j.tet.2006.02.042
日期:2006.5
We have examined several methods for the stereoselective formation of carbon-carbon bonds between contiguous rings where a stereogenic center is already present. The approaches investigated were a [1,3] oxygen to carbon rearrangement of cyclic vinyl acetals, an intermolecular enolsilane addition into an in situ generated oxocarbenium ion, an intramolecular conjugate addition of tethered alkoxy enones
我们已经研究了在立体中心已经存在的连续环之间立体选择性地形成碳-碳键的几种方法。所研究的方法是:环状乙烯基乙缩醛的[1,3]氧至碳重排,在原位生成的氧碳鎓离子中添加分子间烯醇硅烷,拴系的烷氧基烯酮的分子内共轭物添加以及几种α-吡喃基环烷酮的差向异构化。已经发现这些途径在几种情况下是互补的,并且使得能够以优异的产率和优异的非对映选择性形成反式:反式和顺式:反式立体异构体。我们已经通过化学相关性证明了C2-C2'的相对立体化学为1-2。