[2,3]‐Sigmatropic rearrangement reaction involving sulfonium ylide (Doyle–Kirmse reaction) generated from metal carbenes represents one of the powerful methods for the construction of C(sp3)−S and C−C bonds. Although significant advances have been achieved, the asymmetric versions via the generation of sulfonium ylides from metal carbenes have been rarely reported to date, and they have so far been limited to diazo compounds as metal carbene precursors. Here, we describe a copper‐catalyzed enantioselective Doyle–Kirmse reaction via azide‐ynamide cyclization, leading to the practical and divergent assembly of an array of chiral [1,4]thiazino[3,2‐b]indoles bearing a quaternary carbon stereocenter in generally moderate to excellent yields and excellent enantioselectivities. Importantly, this protocol represents a unique catalytic asymmetric Doyle–Kirmse reaction via a non‐diazo approach and an unprecedented asymmetric [2,3]‐sigmatropic rearrangement via α‐imino metal carbenes.

An efficient copper-catalyzed formal [4 + 1] annulation of N-propargyl ynamides with diketones is described. This protocol enables practical and atom-economic synthesis of valuable pyrrole-substituted dioxoles in generally moderate to...

Axially chiral biaryls widely exist in natural products and pharmaceuticals and are used as chiral ligands and catalysts in asymmetric synthesis. Compared to the well-established axially chiral 6-membered biaryl skeletons, examples of 5-membered biaryls have been quite scarce, and mono-substituted 3-arylpyrrole atropisomers have not been reported. Here, we disclose a copper-catalyzed atroposelective diyne cyclization for the construction of a range of axially chiral arylpyrrole biaryls in good to excellent yields with generally excellent enantioselectivities via oxidation and XÀ H insertion of vinyl cations. Importantly, this protocol not only represents the first synthesis of mono-substituted 3arylpyrrole atropisomers, but also constitutes the first example of atroposelective diyne cyclization and the first atropisomer construction via vinyl cations. Theoretical calculations further support the mechanism of vinyl cation-involved cyclization and elucidate the origin of enantioselectivity.

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2,3]-Sigmatropic rearrangement reaction involving sulfonium ylide (Doyle-Kirmse reaction) generated from metal carbenes represents one of the powerful methods for the construction of C(sp 3 )À S and CÀ C bonds. Although significant advances have been achieved, the asymmetric versions via the generation of sulfonium ylides from metal carbenes have been rarely reported to date, and they have so far been limited to diazo compounds as metal carbene precursors. Here, we describe a copper-catalyzed enantioselective Doyle-Kirmse reaction via azide-ynamide cyclization, leading to the practical and divergent assembly of an array of chiral [1,4]thiazino [3,2-b]indoles bearing a quaternary carbon stereocenter in generally moderate to excellent yields and excellent enantioselectivities. Importantly, this protocol represents a unique catalytic asymmetric Doyle-Kirmse reaction via a non-diazo approach and an unprecedented asymmetric [2,3]-sigmatropic rearrangement via α-imino metal carbenes.