Optically active 1,1'-spirobiindane-7,7'-diol (SPINOL)-based phosphoric acids as highly enantioselective catalysts
Chun-Hui Xing1, Yuan-Xi Liao, Jaclynn Ng
1Department of Chemistry, College of Staten Island and the Graduate Center of the City University of New York, Staten Island, New York 10314, United States.
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.
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