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A chiral BINAP-derived phosphoric acid is demonstrated to be an efficient catalyst for the formation of title compounds with adjacent quaternary and tertiary stereogenic centers after alkaline methanolysis.

A highly enantioselective 1,2-aza-Friedel-Crafts reaction of N -tert -butyldimethylsilylindole with N-tert-butoxycarbonyl aromatic imines is demonstrated using a BINOL-derived monophosphoric acid catalyst. The present approach provides efficient access to 3-indolylmethaneamines with aryl substituents in excellent enantioselectivities (up to 98% ee). An inversion in the sense of enantioselection was found between monophosphoric acid catalysts bearing different substituents introduced at the 3,3'-position of binaphthyl backbone. We also calculated the three-dimensional structure of the monophosphoric acid catalysts to speculate on the inversion of the stereochemical outcome.

A new asymmetric entry of the 1,2-aza-Friedel-Crafts reaction catalyzed by a chiral phosphoric acid is described. The present reaction has provided an atom-economical route to furan-2-ylamine derivatives in a highly enantioselective fashion. The synthetic utility of these products was displayed by oxidative cleavage of the furan ring (aza-Achmatowicz reaction) to form a 1,4-dicarbonyl compound that could be further derivatized to a chiral gamma-butenolid.