N, Si-codoped carbon-based iron catalyst for efficient, selective synthesis of pyrroles from nitroarenes: The role of Si doping

The development of novel iron heterogeneous catalysts for organic synthesis is attractive and significant for both academic and industrial applications. A carbon-based iron heterogeneous catalyst (Fe@NSiC) comprising of different iron species including iron atomic single sites (FeN x Si y ), iron silicate and iron nanoparticles (NPs) has been developed. This catalyst exhibits high performance on the solvent-free synthesis of pyrroles from nitroarenes and 2,5-hexanedione via cascade reaction using HCOOH/DBU as the reductant. Si doping can increase Lewis acid sites of the catalyst and the electron density of iron sites, thus promoting the reaction. Furthermore, a set of pyrroles reflecting potential interest from the pharmaceutical perspective are obtained with moderate to excellent yields in this chemistry.