Even alkyl methyl ketones undergo asymmetric hydrogenation with high enantioselectivity when a rhodium complex of the conformationally rigid chiral ligand 1 (Me-PennPhos; R=CH3 ) is used as the catalyst. Basic additives such as 2,6-lutidine contribute to the achievement of high enantiomeric excesses.
当使用构象刚性手性配体1的铑配合物(Me-PennPhos; R = CH 3)作为催化剂时,即使烷基甲基酮也经历高对映选择性的不对称氢化。碱性添加剂(例如2,6-二甲基吡啶)有助于实现高对映体过量。
Chiral Bicyclo[2.2.2]octane‐Fused CpRh Complexes: Synthesis and Potential Use in Asymmetric C−H Activation
作者:Guozhu Li、Xiaoqiang Yan、Jijun Jiang、Hao Liang、Chao Zhou、Jun Wang
DOI:10.1002/anie.202010489
日期:2020.12.7
A new class of chiral cyclopentadienyl rhodium(I) complexes (CpRhI) bearing C2‐symmetric chiral bridged‐ring‐fused Cp ligands was prepared. The complexes were successfully applied to the asymmetric C−H activation reaction of N‐methoxybenzamides with quinones, affording a series of chiral hydrophenanthridinones in up to 82 % yield with up to 99 % ee. Interestingly, structure analysis reveals that the
Syntheses of Novel Chiral Monophosphines, 2,5-Dialkyl-7-phenyl-7-phosphabicyclo- [2.2.1]heptanes, and Their Application in Highly Enantioselective Pd-Catalyzed Allylic Alkylations