Asymmetric Desymmetrization via Metal‐Free C−F Bond Activation: Synthesis of 3,5‐Diaryl‐5‐fluoromethyloxazolidin‐2‐ones with Quaternary Carbon Centers
作者:Junki Tanaka、Satoru Suzuki、Etsuko Tokunaga、Günter Haufe、Norio Shibata
DOI:10.1002/anie.201603210
日期:2016.8
non‐activated aliphatic C−F bond in which a conceptually new desymmetrization of 1,3‐difluorides by silicon‐induced selective C−F bond scission is a key step. The combination of a cinchona alkaloid based chiral ammonium bifluoride catalyst and N,O‐bis(trimethylsilyl)acetoamide (BSA) as the silicon reagent enabled the efficient catalytic cycle of asymmetric Csp3−F bond cleavage under mild conditions with high enantioselectivities
我们公开了非活化脂族CF键的首次不对称活化,其中硅诱导的选择性CF键断裂导致的概念上的1,3-二氟化物的新不对称化是关键步骤。基于金鸡纳生物碱的手性氟化氢铵催化剂和N,O-双(三甲基硅烷基)乙酰胺(BSA)作为硅试剂的组合,可在温和的条件下以高对映选择性有效地催化不对称C sp3- F键断裂。芳基在立体异构中心的邻位作用是显着的。该概念被用于不对称合成有前景的农业化学化合物,带有季碳中心的3,5-二芳基-5-氟甲基恶唑烷-2-酮。