A novel and highly regioselective ammonium iodide-induced nonradical sulfenylation method for the construction of a C-S bond was developed via C-H functionalization. With DMSO or R(1)SO2NHNH2 as a sulfenylating agent, MeS- and R(1)S-substituted flavone derivatives were obtained in good yields. This method enriches current C-S bond formation chemistry, making it a highly valuable and practical method in pharmaceutical industry.

Coumarin and flavone derivatives are highly valuable molecules in drug discovery. Here, two new regioselective cross-dehydrogenation couplings of coumarins and flavones with different ethers via C(sp(3))-H functionalization processes were developed, generating new ether-substituted derivatives not previously reported. These reactions proceeded well via radical mechanisms and provided the corresponding products in good yields.

Two radical-mediated cascade couplings of N-alkyl-N-methacryloylbenzamides with different ethers and arylsulfonohydrazides to generate ether- and arylsulfonyl-substituted isoquinoline-1,3(2H,4H)-dione derivatives were developed. Both casccades proceeded via initially triggered functionalization of the alkene functions of the N-alkyl-N-methacryloylbenzamides, followed by ortho radical cyclizations onto the aromatic ring to give isoquinoline-1,3(2H,4H)-dione derivatives in good yields. These highly functionalized drug-like molecules will be valuable in drug discovery in the future.

Sulfenylation is an important transformation to generate C−S bonds in organic synthesis. Here, two three‐component synthetic protocols have been developed by using imidazo[1,2‐a]pyridine, inorganic, odorless S8 and alcohols or arylboronic acids as reactants to make alkylthio‐/arylthio‐substituted imidazo[1,2‐a]pyridine derivatives via C(sp2)–H functionalization. The reactions proceeded with high efficiency and broad functional group tolerance, affording the products regioselectively and in good yields.magnified image

The method for constructing C-S bonds is very important in organic synthesis. Here a new sulfenylation method to generate flavone thioether derivatives was developed by employing aromatic or alkyl halides, S powder and NaSO as reactants. Good yields of regioselective C-S and C-S-substituted flavones were generated under relatively environmentally friendly and simple conditions. This method might be potentially applicable to large scale production, and it enriches current sulfenylation methods.