The Arnold and Mabel Beckman Laboratory of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA.
J Am Chem Soc. 2010 Jun 30;132(25):8534-5. doi: 10.1021/ja1029045.
The relative TONs of productive and nonproductive metathesis reactions of diethyl diallylmalonate are compared for eight different ruthenium-based catalysts. Nonproductive cross metathesis is proposed to involve a chain-carrying ruthenium methylidene. A second more-challenging substrate (dimethyl allylmethylallylmalonate) that forms a trisubstituted olefin product is used to further delineate the effect of catalyst structure on the relative efficiencies of these processes. A steric model is proposed to explain the observed trends.
比较了八种不同的钌基催化剂中二乙基烯丙基丙二酸酯的生产性和非生产性复分解反应的相对TON 值。非生产性交叉复分解反应被认为涉及链携带的钌亚甲基。使用第二个更具挑战性的底物(二甲基烯丙基甲基烯丙基丙二酸酯)来形成三取代烯烃产物,进一步阐明了催化剂结构对这些过程相对效率的影响。提出了一个空间位阻模型来解释观察到的趋势。