Heteropolyanion-based sulfated ionic liquid catalyzed formamides synthesis by grindstone chemistry

A novel heteropolyanion-based sulfated ionic liquid (HIL-[Ch-OSO3H]3W12PO40) was prepared by pairing sulfate functionalized cholinium cation [N,N,N-trimethyl-2-(sulfooxy)ethanaminium] with catalytically active phosphotungstic acid anion (W12PO403−). It was characterized by 1H NMR, FT-IR, EDX, XRD, TGA and elemental analysis. Catalytic activity of thus prepared HIL was studied in N-formylation of amines under solvent-free grinding condition. The methodology provided cleaner conversion over shorter reaction time with high turnover frequency (TOF) and chemoselectivity.