Shindo Mitsuru, Matsumoto Kenji
Institute for Materials Chemistry and Engineering, Kyushu University, Kasuga, Japan.
Top Curr Chem. 2012;327:1-32. doi: 10.1007/128_2012_313.
The efficient synthesis of tetrasubstituted alkenes by the olefination of carbonyl compounds with ynolates is described. This reaction involves the cycloaddition of ynolates with carbonyl groups, followed by electrocyclic ring-opening of the resulting β-lactone enolates. Orbital symmetry during the electrocyclic ring opening requires conrotatory motion. The direction of this rotation (inward or outward) determines the E/Z geometry to the tetrasubstituted olefin product through torquoselectivity. Theoretical calculations revealed that several secondary orbital interactions are essential for the high torquoselectivity. This methodology is a novel olefination for constructing multisubstituted olefins.
描述了通过羰基化合物与烯醇化物的烯基化反应高效合成四取代烯烃的方法。该反应涉及烯醇化物与羰基的环加成，随后是所得β-内酯烯醇化物的电环化开环。电环化开环过程中的轨道对称性要求进行对旋运动。这种旋转的方向（向内或向外）通过扭转选择性决定了四取代烯烃产物的E/Z几何构型。理论计算表明，几种二级轨道相互作用对于高扭转选择性至关重要。该方法是一种构建多取代烯烃的新型烯基化反应。
