Highly efficient FeNPs embedded hybrid bifunctional reduced graphene oxide for Knoevenagel condensation with active methylene compounds
We have synthesized atypical highly active bifunctional FeNPs implanted on amino-modified reduced graphene oxide (FeNPs/Am@rGO) [where FeNPs = Fe nanoparticles; Am = Primary aromatic amine derivatives such as p-phenylenediamine (PPD) and/or aniline (AN)] nanocatalysts with acid-base dual-activation mechanism by introducing primary aromatic amines on the basal and/or edges sites of rGO offering a base characteristic and FeNPs anchored onto the surface of rGO supplying Lewis acidic nature. These nanocatalysts were well corroborated through assorted physicochemical techniques. Impressively, FeNPs/Am@rGO significantly promoted a one-pot Knoevenagel condensation reaction with different aromatic aldehydes and active methylene compounds bestowing excellent activity to give synthetically valuable multifunctional benzylidene derivatives. The impact of discrete parameters influencing catalytic activity has also been monitored. Under the optimized stipulations, FeNPs/PPD@rGO exclusively promoted the aforementioned reaction leading to 100% benzaldehyde conversion with a 100% yield of the product along with TON and TOF (h-1) values are 350.8 and 100.2, respectively. Besides this, it could be effortlessly recycled by centrifugation after each run and afterward reused without momentous loss of its catalytic activity in a six cycles test.