A new class of chiral phosphoric acids with spirobiindane as scaffold were conveniently synthesized from (S)-1,1'-spirobiindane-7,7'-diol ((S)-SPINOL) and employed to catalyze the asymmetric Friedel-Crafts reaction of indoles with imines to afford 3-indolyl methanamines. High yields (68-97%) and excellent enantioselectivities (up to 99% ee) were obtained.

The discovery of proper ligands to simultaneously modulate the reactivity and effectively control the stereoselectivity is a central topic in the field of enantioselective C−H activation. Herein, we reported the synthesis of axially chiral biaryls by Pd‐catalyzed atroposelective C−H olefination. A novel chiral spiro phosphoric acid, STRIP, was identified as a superior ligand for this transformation. A broad range of axially chiral quinoline derivatives were synthesized in good yields with excellent enantioselectivities (up to 98 % ee). Density functional theory was used to gain a theoretical understanding of the enantioselectivities in this reaction.

An efficient organocatalytic atroposelective threecomponent cascade reaction of 2,3-diketoesters,a romatic amines,a nd 1,3-cyclohexanediones has been developed for the highly enantioselective synthesis of axially chiral Narylindoles.T he success of this method derives from the use of an ewly developed second-generation chiral spirocyclic phosphoric acid as the catalyst. In addition, this protocol was extended to the synthesis of an axially chiral monophosphorus ligand.

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The development of suitable chiral catalysts, which represent powerful, economically feasible tools for the preparation of optically active organic molecules, is a fundamental endeavour in synthetic chemistry. Chiral phosphoric acids derived from axially chiral 1,1'-bi-2-naphthol (BINOL) are a widely used class of strong Brønsted acid catalysts and have been applied successfully in many asymmetric catalyzed reactions. Accordingly, the development and application of chiral spirocyclic phosphoric acids derived from axially chiral 1,1'-spirobiindane-7,7'-diol (SPINOL) have received increasing attention in the last eight years. This review covers the synthetic methods and the application of chiral spirocyclic phosphoric acids in asymmetric catalysis.