The extensively developed ene-type enantioselective cycloisomerization of classical 1,n-enynes provides an efficient approach to chiral cyclic 1,4-dienes.I nc ontrast, the catalytic asymmetric heteroarenyne (heteroarene-alkyne) cycloisomerization involving the dearomative transformation of endocyclic aromatic C = Cb onds remains unknown. Herein, we communicate aPdH-catalyzed enantioselective heteroarenyne cycloisomerization reaction of alkyne-tethered indole substrates (formal 1,5-and 1,6-enynes). Based on this strategy, avariety of structurally diverse chiral spiro and fused indoline derivatives bearing quaternary stereocenters and exocyclic C = Cb onds are afforded in moderate to excellent yields and excellent enantioselectivities (up to 98 %ee). The classical enetype enantioselective 1,5-enyne cycloisomerization of N-vinylpropiolamides is also developed to affordc hiral 2-pyrrolones in good to excellent ee values. Scheme 1. Ene-type enantioselective enyne and heteroarenynecycloisomerization.

An efficient cobalt­(III)-catalyzed method for the direct C–H amidation of unprotected indoles for 2-amino indole scaffold construction has been developed. With dioxazolone as the amidating reagent, a variety of 2-amino indole derivatives were achieved in moderate to excellent yields using an organic acid as the additive and a ketone as the directing group.

A palladium-catalyzed intramolecular enantioselective Mizoroki–Heck reaction of naphthalenes has been developed via dearomative migratory insertion of an endocyclic π-bond of naphthalene, followed by δ-hydride elimination. This reaction relies on the use of chiral sulfonamide phosphine type Xu-Phos ligand, which successfully inhibits the competitive and undesired C–H arylation reaction and efficiently promotes the formation of spirooxindole and spiroisoindolin-1-one products. Synthetic transformations of the product afford a series of unique heterocyclic compounds with enantiomeric excess (ee) values retained.

An efficient and facile method to synthesize valuable disubstituted 2-aryl indoles and benzofurans in good yields has been demonstrated, based on a tert-butoxide-mediated condensation reaction involving a vinyl sulfoxide intermediate. Products are obtained from N- or O-benzyl benzaldehydes using dimethyl sulfoxide as a carbon source. The methodology features a wide functional group tolerance and transition metal-free environment. Preliminary mechanistic studies suggest that the reaction involves a tandem aldol reaction/Michael addition/dehydrosulfenylation/isomerization sequence through an ionic protocol.

The extensively developed ene‐type enantioselective cycloisomerization of classical 1,n‐enynes provides an efficient approach to chiral cyclic 1,4‐dienes. In contrast, the catalytic asymmetric heteroarenyne (heteroarene–alkyne) cycloisomerization involving the dearomative transformation of endocyclic aromatic C=C bonds remains unknown. Herein, we communicate a PdH‐catalyzed enantioselective heteroarenyne cycloisomerization reaction of alkyne‐tethered indole substrates (formal 1,5‐ and 1,6‐enynes). Based on this strategy, a variety of structurally diverse chiral spiro and fused indoline derivatives bearing quaternary stereocenters and exocyclic C=C bonds are afforded in moderate to excellent yields and excellent enantioselectivities (up to 98 % ee). The classical ene‐type enantioselective 1,5‐enyne cycloisomerization of N‐vinylpropiolamides is also developed to afford chiral 2‐pyrrolones in good to excellent ee values.