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Catalytic enantioselective hydroarylation of alkynes is a concise protocol towards axial, helical, and planar chirality, but most reactions involve noble-metal catalysts. Here, the authors report a copper-catalyzed intramolecular atroposelective hydroarylation of 1-alkynylindoles with (hetero)arenes, affording C─N axially chiral carbazolyl and phenanthryl indoles.

Fused N-heterocycles are structural motifs observed in natural products and bioactive compounds. Here, the authors developed divergent copper- and gold-catalyzed oxidative cyclizations of diynes to two types of tricyclic N-heterocycles and rationalized the product selectivity by theoretical calculations.

One-carbon ring expansion reaction of heteroarenes involving typical dearomative cyclopropanation has gained wide attention in the past decade as it allows the facile synthesis of various valuable ring-expanded heterocycles. Herein, the authors report an enantioselective dearomative one-carbon ring expansion of benzofurans via vinyl cations formed by copper-catalyzed cyclization of diynes.

Divergent catalytic asymmetric reactions for the selective formation of C(sp3)−H insertion and formal C(sp3)−O insertion products from the same precursors are rarely explored. Here, the authors report a ligand-controlled divergent asymmetric C(sp3)–H insertion and formal C(sp3)–O insertion reaction via vinyl cations, leading to the assembly of a range of chiral spiro and fused polycyclic pyrroles.

One-carbon insertion into N–O bonds is widely exploited in organic synthesis, but synthetic protocols for this rely on hazardous diazo precursors that are difficult to access. Here, copper-catalyzed intermolecular formal (5 + 1) annulation of 1,5-diynes with 1,2,5-oxadiazoles is shown to facilitate one-carbon insertion into heterocyclic N–O bonds without the need for diazo precursors.

Asymmetric Büchner reactions are an effective methodology to bring about synthetic complexity from the common benzene motif, but effective, general catalytic methods are scarce. Here, the authors present divergent asymmetric arene dearomatization from ynamides using copper catalysis, wherein the catalytic cycle proceeds via a putative vinyl cation intermediate.

Site- and stereoselective C–H functionalization is challenging in the synthetic chemistry, and the catalytic enantioselective C(sp3)–H functionalization based on vinyl cations has scarcely explored. Here, the authors report an asymmetric copper-catalyzed tandem diyne cyclization/unactivated C(sp3)–H insertion reaction via a kinetic resolution.

The formal C–C bond insertion into aldehydes is an attractive methodology for the assembly of homologated carbonyl compounds but the homologation of aldehydes has been limited to diazo approach and the enantioselective reaction was rarely developed. Here, the authors report an asymmetric formal C–C bond insertion into aldehydes through diyne cyclization strategy

Chiral Brønsted acid catalysis is mostly limited to the activation of imine and carbonyl moieties. Now, by direct activation of alkynes, chiral Brønsted acids have been used to enable the catalytic asymmetric dearomatization of naphthol-, phenol- and pyrrole-ynamides for the construction of various spirocyclic enones and 2H-pyrroles bearing a chiral quaternary carbon stereocentre.

Stereospecific [1,3]-rearrangements are rarely reported method to efficiently build complex organic architectures. Here, the authors describe a metal-free intramolecular hydroalkoxylation/[1,3]-rearrangement sequence affording medium-sized lactams with wide scope, also in an asymmetric fashion.

The asymmetric synthesis of chiral γ-lactams is difficult and laborious; typically requiring pre-functionalization of starting materials. Now, a highly efficient alternative approach employing direct C−H amidation via chiral hydrogen-bond-donor catalysts has been developed.