Yadong Feng

Copper-Catalyzed Synthesis of 2-Arylquinazolinones from 2-Arylindoles with Amines or Ammoniums.

A novel copper-catalyzed synthesis of quinazolinones from easily available 2-arylindoles and amines or ammoniums has been developed, which provided various quinazolinones in up to 99% yields for 43 examples. This strategy features tolerance of a wide range of functional groups, easily available starting materials, simple operation, mild reaction conditions, and environmental friendliness.

A metal-free synthesis of diaryl-1,2-diketones by C–C triple bond cleavage of alkynones

A novel and environmentally benign protocol for diaryl-1,2-diketones was developed. Various diaryl-1,2-diketones were afforded in moderate to excellent yields by C–C triple bond cleavage of alkynones using molecular oxygen as an oxidant. A plausible reaction mechanism was proposed that accounts for all the experimental results. The products are important building blocks in organic synthesis and could be converted to various synthons via diverse transformations.

Iridium(III)-Catalyzed One-Pot Access to 1,2-Disubstituted Benzimidazoles Starting from Imidamides and Sulfonyl Azides

A novel Ir-catalyzed annulation of imidamides with sulfonyl azides has been developed. 1,2-Disubstituted benzimidazoles could be easily obtained in up to 99% yield for more than 40 examples. The products further streamline the synthesis of molecules that are important building blocks for organic synthesis and drug discovery. This strategy features high regioselectivity, efficiency, good tolerance of functional groups, and mild reaction conditions.

Construction of Fused Polyheterocycles through Sequential [4 + 2] and [3 + 2] Cycloadditions

A method for Pd-catalyzed aerobic oxidative reaction of quinazolinones and alkynes has been developed for sequential [4 + 2] and [3 + 2] cycloadditions to assemble a novel fused-polycyclic system containing tetrahydropyridine and dihydrofuran rings. The reaction process involves C-H and N-H bond functionalization for the formation of tetrahydropyridine and an oxygen radical cyclization for the dihydrofuran ring. This atom- and step-economical synthesis is highly efficient and has good substrate tolerance, which provides a new approach for the construction of polycyclic molecules with potential pharmaceutical interest.

One-Pot Access to peri-Condensed Heterocycles via Manganese-Catalyzed Cascade C–N and C–C Bond Formation

A Mn(III)-catalyzed three-component cascade C-H/N-H functionalization of 2-aminopyridines with 2 equiv of dialkyl butyndioates leads to peri-condensed tricylic azines through a selective, but partly destructive, stoichiometry. A wide range of 2,11-diazatricyclo[5.3.1.04,11]undeca-1(10),4,6,8-tetraen-3-ones were thus obtained with moderate to high yields in a step-economical fashion under mild conditions. This transformation can serve as a concise method for constructing valuable precursors of functional materials and biologically active compounds.

Iridium-catalysed direct sulfamidation of quinazolinones

Ir-catalysed direct sulfamidation of quinazolinones has been achieved. A series of ortho-diamided quinazolinones were obtained in up to 96% yields. This transformation could proceed smoothly with a low catalyst loading under mild conditions with nitrogen released as the sole byproduct. This approach potentially provides an environmentally benign sulfamidation process for atom/step economic syntheses of useful pharmaceutical molecules or important building blocks.