Mechanical milling promotes the preparation of catalyst lanthanum dodecyl sulfate and green solvent-free grinding for synthesis of N-heterocyclic derivatives

Abstract

The lanthanum dodecyl sulfate catalyst (La(DS)3) was synthesized using a solvent-free mechanical ball method and applied in the preparation of solvent-free N-heterocyclic compounds. The preparation of the La(DS)3 catalyst and the synthesis of C-N bond series compounds only require brief ball milling of the mixed material at room temperature. Various analyses such as SEM, HRTEM, XRD, AFM, FT-IR, XPS, TGA, and DFT were conducted, which showed that the catalyst material synthesized by mechanical ball milling exhibited superior catalytic activity, thermal stability, and cyclic life compared to similar materials synthesized in an aqueous phase. The solvent-free catalytic synthesis of quinoxaline, dihydroacridin-1(2H)-one, and bis(indolyl)methanes derivatives achieved excellent target yields. Furthermore, the catalyst could be reused at least seven times without a significant decrease in activity after simple treatment. The catalyst also demonstrated gram scale scaling up in the model reaction. It exhibited weak hydrophilicity and a stable network-like layered nanostructure.