Recyclable ZnIn2S4 Microspheres for Photocatalytic Azolation of N-Heterocycles

A series of zinc indium sulfide (ZnIn2S4) were synthesized by solvothermal methods in different solvents. After characterizations, the ZnIn2S4 prepared in ethanol (i.e., ZIS-1) showed the highest photocurrent density. With the ZIS-1 as a photocatalyst, the direct C-H azolation of N-heterocycles including quinoxalin-2(1H)-ones, quinazoline, and 2H-benzo[b]-[1,4]oxazin-2-ones (32 examples) was realized in an air atmosphere under blue light (456 nm). More importantly, the microspherical photocatalyst ZIS-1 is stable in the catalytic process and can be used at least five times while the reactivity remains unchanged. In addition, this practical approach is also applicable to some other complex molecules of interest, such as ibuprofen and isoxepac.

Automated summary

A series of zinc indium sulfide (ZnIn2S4) photocatalysts were successfully synthesized, with the catalyst ZIS-1 prepared in ethanol showing the highest photocurrent density. Using ZIS-1 as a photocatalyst, the direct C-H azolation of N-heterocycles was achieved under blue light, and the catalyst exhibited good stability and reusability.