Asymmetric Allylboration of Aldehydes with Pinacol Allylboronates Catalyzed by 1,1′-Spirobiindane-7,7′-diol (SPINOL) Based Phosphoric Acids
作者:Chun-Hui Xing、Yuan-Xi Liao、Yimei Zhang、Darya Sabarova、Monica Bassous、Qiao-Sheng Hu
DOI:10.1002/ejoc.201101739
日期:2012.2
The asymmetricallylboration of aldehydes with pinacolallylboronates catalyzed by 1,1′-spirobiindane-7,7′-diol (SPINOL) basedphosphoricacids is described. 6,6′-Bis(2,4,6-triisopropylphenyl)SPINOL-based phosphoricacid was found to be a general, highly enantioselective catalyst for such allylboration reactions and excellent enantioselectivities were obtained for different types of aldehydes including
Asymmetric <i>N</i>-Hydroxyalkylation of Indoles with Ethyl Glyoxalates Catalyzed by a Chiral Phosphoric Acid: Highly Enantioselective Synthesis of Chiral <i>N,O</i>-Aminal Indole Derivatives
A method of SPINOL-derived chiralphosphoricacidcatalyzedasymmetric intermolecular N-hydroxyalkylation of multisubstituted indoles with ethyl glyoxalates is described in this report. This protocol provides an alternative, convenient, and direct strategy for efficient access to structurally unique α-chiral indole N,O-acyclic aminals with a broad substrate scope and good to excellent enantioselectivities