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In the presence of ( R )-SEGPHOS-PdCl 2 catalyst, 5- endo -hydroaminocyclization of various 2-( tert -butyl)- N -(2-ethynylphenyl)anilines proceeds enantioselectively to afford optically active N–C axially chiral N -(2- tert -butylphenyl)indole derivatives in good yields. The enantioselectivity depends strongly on the bulkiness of ortho -substituents and the electron density on the arylethynyl group, and it is explained by the dynamic axial chirality generated by the twisting of the aryl substituent. [ABSTRACT FROM AUTHOR]

Axially chiral N -arylindoles and realated compounds were stereoselectively synthesized using the following three protocols; 1) diastereoselective nucleophilic aromatic substitution, 2) desymmetrization via a stereoselective Cr(CO) 3 migration reaction, and, 3) catalytic enantioselective synthesis via asymmetric ring-closing metathesis. Arene chromium tricarbonyls were utilized as key building blocks, and all of these methods induced extremely high stereoselectivities. Moreover, Cr(CO) 3 fragments were easily removed via air oxidation condition to afford Cr-free N -arylindoles with axially chiral N–C bonds. [ABSTRACT FROM AUTHOR]