Hang-Dong Zuo

A catalyst- and oxidant-free annulative chloro-hydroxylamination of enynones with anomeric amides has been developed, enabling the efficient synthesis of diverse 1-indanone frameworks via a radical chain process. This protocol features outstanding regioselectivity, broad substrate scope, excellent functional-group tolerance, mild reaction conditions, and high atom economy. Notably, this environmentally friendly strategy eliminates the need for hazardous catalysts and oxidants, fully adhering to the principles of green chemistry.

A copper-catalyzed annulation–trifunctionalization of enynones using Togni's reagent and H ₂ O affords trifunctionalized indenes. Notably, the ligand plays a triple role as a copper-coordinating agent, a Brønsted base, and a proton shuttle.

A new method for making N-haloimines by Mn-catalyzed radical haloazidation of 1,5-enenitriles with TMSN₃ and N-halosuccinimides is introduced. The resulting azido N-haloimines are used for diannulation with alkynes to form triazole-fused heterocycles via a cascade CuAAC with alkynes and intramolecular electrophilic aromatic substitution (EAS).

This work presents a Cu-catalyzed radical-initiated spirocyclization–oxytrifluoromethylation to synthesize spirobutyl quinolones under mild conditions. The products show late-stage reactivity, with one serving as a dual optical sensor for Cr ⁶⁺ /Ba ²⁺ .

A novel type of alkynyl-containing BCBs was prepared and then applied to radical-triggered annulation-haloazidation via a three-component reaction, enabling the synthesis of halo-azide substituted spiro-cyclobutyl quinolinones.

The novel copper-catalyzed radical-triggered annulation-halocyanomethylation reaction, involving preprepared alkynyl-substituted bicyclo[1.1.0]butanes (BCBs) and haloacetonitrile, was reported for the first time, enabling the synthesis of various halocyanomethylated spirocyclobutyl quinolinones with moderate to high yields and perfect regioselectivity. This method exhibits broad substrate adaptability and exceptional functional group tolerance and is distinguished by its capacity to directly form up to three new chemical bonds while constructing a spirocyclic framework in a single step.

Two separate classes of three-component radical-initiated annulation-bifunctionalization reactions involving indole-linked 1,6-enynes have been successfully established under mild reaction conditions. The oxidant-mediated annulation-iodonitration employs tert-butyl nitrite and iodoform as reagents, while the palladium-catalyzed annulation-aryldifluoroalkylation utilizes difluoroiodoacetate and arylboronic acids as starting materials. In combination, these two reaction models have promoted the synthesis of functionalized pyrrolo[1,2-a]indoles, with stereoselectivity values varying from a 1:1 ratio to a 19:1 ratio. A total of 30 examples are provided to validate the efficacy of these methods. Furthermore, the obtained products exhibit excellent potential for subsequent modifications. The proposed reaction mechanisms have been thoroughly clarified through a series of meticulously designed control experiments. These newly devised protocols open up promising new pathways for the rapid construction of functionalized pyrrolo[1,2-a]indole frameworks with generally acceptable yields.

We develop a photoredox-catalyzed three-component deconstructive alkynylsulfonylation and vinylsulfonylation reaction of spiro-dihydroquinazolinones with alkynyl or vinyl halides and DABSO through the insertion of sulfur dioxide, providing the alkynyl and vinyl sulfones in generally good yields. Notably, this photocatalytic system can be expanded to synthesize relevant alkynylated and alkenylated quinazolinones when the reaction is conducted in the absence of DABSO under the standard conditions. More importantly, the resulting alkynyl sulfones were found to exhibit typical aggregation-induced emission properties in the mixture of THF/H₂O and could be applied to copper catalyzed [3 + 2] cycloaddition, establishing a versatile strategy for synthesizing a triazole unit and sulfonyl group-anchored quinazolinones.

The photocatalyzed difluoroamidoalkylation and three-component difluoroamidosulfonylation have been established for the synthesis of trifunctionalized enamides with generally moderate yields along with outstanding regio- and stereoselectivity.

A photocatalytic radical-mediated strategy has been developed for the 1,5-hydrogen atom transfer (1,5-HAT)/alkenylation of hydroxamides with enamides, enabling the efficient synthesis of trisubstituted enamides in moderate to good yields.