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of main observation and conclusion A new class of axially chiral aryl-alkene-indole frameworks have been designed, and the first catalytic asymmetric construction of such scaffolds has been established by the strategy of organocatalytic (Z/E)-selective and enantioselective (4+3) cyclization of 3-alkynyl-2-indolylmethanols with 2-naphthols or phenols (all >95 : 5 E/Z, up to 98% yield, 97% ee). This reaction also represents the first catalytic asymmetric construction of axially chiral alkene-heteroaryl scaffolds, which will add a new member to the atropisomeric family. This approach has not only confronted the great challenges in constructing axially chiral alkene-heteroaryl scaffolds but also provided a powerful strategy for the enantioselective construction of axially chiral aryl-alkene-indole frameworks.

Atroposelective synthesis of axially chiral molecules has attracted substantial attention from chemists because of the importance of such molecules. However, catalytic asymmetric synthesis of axially chiral styrenes or vinyl arenes is underdeveloped and challenging due to the low rotational barrier and weak configurational stability of such molecules. Therefore, the development of powerful strategies for the catalytic atroposelective synthesis of axially chiral styrenes or vinyl arenes is of great importance. In this work, we have accomplished the first atroposelective access to oxindole-based axially chiral styrenes by the strategy of catalytic kinetic resolution, and this strategy offered two kinds of oxindole-based axially chiral styrene derivatives in good diastereoselectivities (up to 94:6 dr) and excellent enantioselectivities (up to 98% ee) with high selectivity factors (S up to 106). This strategy not only provides easy access to oxindole-based axially chiral styrenes but also offers a robust method for synthesizing bisamide derivatives bearing both axial and central chirality. More importantly, this strategy has added a new class of members to the atropisomeric family, especially to the family of axially chiral styrenes.

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