Structure–enantioselectivity correlation in NHC–Au(I) catalysis for 1,6-enynecyclizations
作者:Benjamin W. Gung、Michael R. Holmes、Caleb A. Jones、Ruoyu Ma、Charles L. Barnes
DOI:10.1016/j.tetlet.2016.07.046
日期:2016.8
A direct correlation of the NHC ligand structure and the induced enantioselectivity has been uncovered for a series of new chiral gold(I) complexes. The Au(I)Cl complexes were identified by 1H, 13C NMR spectroscopy, and X-ray structure analysis. The corresponding activated Au(I) catalysts with a phenyl nitrile dynamic ligand are prepared and used in the catalysis of 1,6-enyne cyclization reactions
对于一系列新的手性金(I)配合物,已经发现了NHC配体结构和诱导的对映选择性的直接相关性。通过1 H,13 C NMR光谱和X射线结构分析鉴定Au(I)Cl络合物。制备具有苯基腈动态配体的相应活化的Au(I)催化剂,并将其用于1,6-烯炔环化反应的催化中。用6%的手性NHC–Au(I)催化剂可获得高化学产率和良好的对映选择性。这些反应中的产物可达到75%ee。手性NHC配体的结构,其中邻-联苯基部分与氮原子相连,远端3,5-二烷基苯基在对映选择性中起决定性作用。