Exploiting Phosphonate Chemistry in Metal-Mediated Dearomatization: Stereoselective Construction of Functionalized Spirolactams from Arene Ruthenium Complexes
作者:F. Christopher Pigge、John J. Coniglio、Rashmi Dalvi
DOI:10.1021/ja058342y
日期:2006.3.1
possessing beta-amido phosphonate side chains participate in intramolecular spirocyclization reactions to deliver stable cyclohexadienyl ruthenium adducts. Spirocyclization is accomplished via a tandem two-step sequence that involves stereoselective nucleophilic aromatic addition to the ipso position of the coordinated arene, followed by intermolecular Horner-Wadsworth-Emmons olefination. The resulting
具有β-氨基膦酸酯侧链的芳烃钌配合物参与分子内螺环化反应以提供稳定的环己二烯基钌加合物。螺环化是通过串联的两步序列完成的,包括立体选择性亲核芳香加成到配位芳烃的 ipso 位置,然后是分子间 Horner-Wadsworth-Emmons 烯化。在合适的亲核试剂的存在下,通过氧化脱金属,所得的eta5-环己二烯基配合物可以非对映选择性地转化为不含金属的氮杂螺[4.5]癸烷衍生物。通过将此过程应用于由 (S)-(-)-α-甲基苄胺制备的 β-酰胺基膦酸酯,证明了不对称螺环化。获得预期的螺内酰胺产物,为单一对映异构体。