A highly efficient copper-catalyzed asymmetric addition of terminal alkynes to isatins has been developed. In the presence of a catalytic amount of copper iodide and a chiral phosphine ligand, the reaction gave the corresponding chiral 3-alkynyl-3-hydroxyindolin-2-ones in high yields with high enantioselectivity. This methodology has a broad substrate scope, and the synthetic utility of the present protocol was further demonstrated by the transformation of chiral alkynylation products.

The direct oxidation of internal alkynes proceeds efficiently in the presence of CuI as a catalyst to afford the corresponding 1,2-diketones in good yields. This strategy offers a simple and efficient route for the synthesis of 1,2-diketones from an inexpensive copper catalyst and easily available internal alkynes. The advantage of present protocol is further demonstrated by the synthesis of quinoxaline derivatives from alkynes and 1,2-diaminobenzene via one-pot procedure.

A novel protocol for the transamidation of DMF and derivatives with weakly nucleophilic anilines has been developed, utilizing a catalytic amount of Pd(OAc)2 and 2,2′-bipyridine, and with PivOH and BF3·Et2O as additives. This methodology has a broad substrate scope, and various corresponding transamidation products were prepared in good to excellent yields from commercially available DMF derivatives and anilines. The synthetic utility of the reported protocol was further demonstrated with a gram-scale experiment. Control experiments suggested the efficient transformation of DMF and derivatives with anilines might owe to the synergistic effect of palladium complex, PivOH, and BF3·Et2O.

The annulation of heteroaromatic β-halo-α,β-unsaturated carboxylic acids with alkynes proceeds efficiently in the presence of Cu(OAc)2·H2O as a catalyst to afford the corresponding indolo[2,3-c]pyrane-1-ones and thieno[2,3-c]pyrane-7-ones in moderate to good yields. This strategy offers a simple and efficient route for the synthesis of indolo[2,3-c]pyrane-1-ones and thieno[2,3-c]pyrane-7-ones with good tolerance to a variety of functional groups from easily available heteroaromatic β-halo-α,β-unsaturated carboxylic acids.

The addition of o-halobenzoic acids to active internal alkynes proceeds efficiently in the presence of CuCl2 as a catalyst to give the corresponding isocoumarin derivatives in moderate to good yields. This strategy offers a simple, efficient route to synthesis of the isocoumarin derivatives.

The annulation of heteroaromatic β-halo-α,β-unsaturated carboxylic acids with alkynes proceeds efficiently in the presence of Cu(OAc)2·H2O as a catalyst to afford the corresponding indolo[2,3-c]pyrane-1-ones and thieno[2,3-c]pyrane-7-ones in moderate to good yields. This strategy offers a simple and efficient route for the synthesis of indolo[2,3-c]pyrane-1-ones and thieno[2,3-c]pyrane-7-ones with good tolerance to a variety of functional groups from easily available heteroaromatic β-halo-α,β-unsaturated carboxylic acids.