title: Optically active 1,1'-spirobiindane-7,7'-diol (SPINOL)-based phosphoric acids as highly enantioselective catalysts for asymmetric organocatalysis.
abstract: The synthesis and application of a series of optically active 1,1'-spirobiindane-7,7'-diol (SPINOL)-based phosphoric acids are described. These SPINOL-based phosphoric acids were prepared from (R)-SPINOL in three steps and exhibited excellent enantioselectivities for the reactions of indoles with aldimines and β,γ-unsaturated-α-ketoesters. Our study provides a family of promising chiral phosphoric acids to the asymmetric organocatalysis toolbox.
authors.affiliation: Department of Chemistry, College of Staten Island and the Graduate Center of the City University of New York, Staten Island, New York 10314, United States.
authors.forename: Chun-Hui
authors.initials: CH
authors.lastname: Xing
authors.forename: Yuan-Xi
authors.initials: YX
authors.lastname: Liao
authors.forename: Jaclynn
authors.initials: J
authors.lastname: Ng
authors.forename: Qiao-Sheng
authors.initials: QS
authors.lastname: Hu