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Axially chiral biaryl diols have achieved great success in asymmetric catalysis. By contrast, axially chiral biaryl amino alcohols are far less developed. Herein, we have rationally designed a versatile C 1 -symmetric biaryl amino alcohol scaffold 1-(1-amino-pyrrol-2-yl)naphthalen-2-ol (NPNOL) on the basis of axially chiral C2-arylpyrrole framework. For its enantioselective synthesis, the chiral phosphoric acid-catalyzed asymmetric Attanasi reaction between 1,3-dicarbonyl compounds and azoalkenes had been established. By using this practical method, a wide range of NPNOLs were readily prepared in high yields and excellent atroposelectivities (38 examples, up to 89 % yield and 99 % ee). DFT calculations were performed to reveal the reaction mechanism and the origins of the enantioselectivity. The easy transformations of NPNOL-derived products into organocatalysts/ligands and their preliminary applications in asymmetric catalytic reactions demonstrated the promising utility of NPNOL., (© 2022 Wiley-VCH GmbH.)

The enantioselective dearomatization of indoles by an organocatalytic (3+2) reaction has been established. The reaction makes use of simple indole derivatives as substrates, and employs azoalkenes reaction partners. A wide range of pyrroloindolines containing an all-carbon quaternary stereogenic center were readily prepared in high yields and with excellent enantioselectivities., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Construction of contiguous all-carbon quaternary stereogenic centers is a long-standing challenge in synthetic organic chemistry. In this report, a phosphine-catalyzed enantioselective (3+2) annulation reaction between allenes and isoindigos, containing either two identical or different oxindole moieties, is introduced as a powerful strategy for the construction of spirocyclic bisindoline alkaloid core structures. The reported reactions feature high chemical yields, excellent enantioselectivities, and very good regioselectivities, and are highly useful for creating structurally challenging bisindoline natural products., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The first catalytic asymmetric construction of 3,3'-bisindole skeletons bearing both axial and central chirality has been established by organocatalytic asymmetric addition reactions of 2-substituted 3,3'-bisindoles with 3-indolylmethanols (up to 98 % yield, all >95:5 d.r., >99 % ee). This reaction also represents the first highly enantioselective construction of axially chiral 3,3'-bisindole skeletons, and utilizes the strategy of introducing a bulky group to the ortho-position of prochiral 3,3'-bisindoles. This reaction not only provides a good example for simultaneously controlling axial and central chirality in one operation, but also serves as a new strategy for catalytic enantioselective construction of axially chiral 3,3'-bisindole backbones from prochiral substrates., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The first catalytic asymmetric [2+3] cyclization of azlactones with azonaphthalenes has been established. This strategy allowed the synthesis of a variety of chiral isatin derivatives in generally good yields and excellent enantioselectivities (up to 99 % yield, 98 % ee). The developed reaction has not only established a catalytic enantioselective [2+3] cyclization using azlactones as two-carbon building blocks, but also enriches the chemistry of catalytic asymmetric cyclizations of azonaphthalenes. In addition, this protocol will provide a useful method for constructing enantioenriched 3,3'-disubstituted isatin-type frameworks., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The first enantioselective construction of a new class of axially chiral naphthyl-indole skeletons has been established by organocatalytic asymmetric coupling reactions of 2-naphthols with 2-indolylmethanols (up to 99 % yield, 97:3 e.r.). This approach not only affords a new type of axially chiral heterobiaryl backbone, but also provides a new catalytic enantioselective strategy for constructing axially chiral biaryl scaffolds by making use of the C3-electrophilicity of 2-indolylmethanols., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)