No abstract

The first copper-catalyzed oxysulfonylation reaction of alkenes with dioxygen and sulfonylhydrazides for the construction of β-ketosulfones has been developed under mild conditions without any ligand or additive.

A direct and straightforward approach for highly regioselective thiocyanation of imidazoheterocycles through sp(2) C-H functionalization has been realized at room temperature. Various C-3 thiocyanated imidazopyridines are formed in moderate to good yield. The present method exhibits a mild and selective access to a variety of imidazopyridine derivatives of pharmacological interest.

A novel and efficient visible-light-induced C(sp 2 )−H/N−H cross-dehydrogenative coupling (CDC)amination with both primary and secondary aliphatic amines at room temperature in air is developed. This photocatalytic reaction allows the direct formation of 3-aminoquinoxalin-2(1H)-ones via CDC-amination in the absence of any external oxidant added from outside. Preliminary mechanistic studies reveal that the present reaction proceeds through a radical process.

A convenient and practical metal-free visible-light-promoted method to synthesize 3-oxyalkylated quinoxalin-2­(1H)-ones was developed at room temperature. The present transformation could be accomplished through Rose Bengal-catalyzed C–H/C–H cross-dehydrogenative-coupling of quinoxalin-2­(H)-ones with simple ethers, providing an efficient and operationally simple method to access various 3-oxyalkylated quinoxalin-2­(1H)-ones with moderate to good yields.

Highly efficient visible-light initiated direct oxysulfonylation of alkenes with sulfinic acids leading to β-ketosulfones has been realized under metal-free conditions.

A simple and convenient approach for the construction of β-iodovinyl sulfones has been developed via direct difunctionalization of alkynes with sulfinic acids and molecular iodine.

We have successfully developed a green and efficient multicomponent reaction protocol to synthesize S-aryl dithiocarbamates under visible light. Most appealingly, the reaction can proceed smoothly without adding any transition-metal catalysts, ligands, or photocatalysts while minimizing chemical wastes and metal residues in the end products. The advantages of this method meet the requirements of sustainable and green synthetic chemistry, and it provides a straightforward way to create valuable S-aryl dithiocarbamates.