Axially chiral styrene-based organocatalysts and their application in asymmetric cascade Michael/cyclization reaction

Abstract

An axially chiral styrene-based organocatalyst, featuring a combination of axially chiral styrene-based structure and a pyrrole ring, has been designed and synthesized. This catalyst demonstrates remarkable capabilities in producing a...

Regioselective Electrooxidative [3+2] Annulation between Indole and Aniline Derivatives to Construct Functionalized Indolo[2,3-b]indoles

“…Given these promising properties, the approach for constructing an indolo­[2,3- b ]­indole scaffold has aroused a great deal of attention. − In general, indolo­[2,3- b ]­indoles are generally synthesized from 2-nitroarylboronic acids and 3-halogenated indoles through Suzuki cross-coupling, which is then followed by the intramolecular reductive cyclization. − However, the direct [3+2] annulation between alkenes and anilines has become a more attractive and efficient approach for constructing the five-membered heterocycle of indolo­[2,3- b ]­indoles, which does not require the modification of complex functional groups on the substrates beforehand. − Our group has reported a chiral phosphoric acid-catalyzed intermolecular [3+2] annulation to furnish the tetra-hydroindole pyrazolinones in good yields with excellent enantioselectivities (Scheme b). − …”

Stereoselective Sulfa-Michael/Aldol Reaction Promoted by an Axially Chiral Styrene-Based Organocatalyst

“…On the basis of our group’s interest in the synthesis of axially chiral compounds and heterocyclic compounds, we have successfully designed and developed axially chiral organocatalysts that have been specifically applied to facilitate the asymmetric sulfa-Michael/aldol reaction between enynamides and thioaldehydes (Scheme b). This strategic approach has proven to be highly efficient in the synthesis of chiral tetrahydrothiophene compounds, exhibiting remarkable levels of enantioselectivity and diastereoselectivity.…”