N–Formylation of Amines Over a Protonic Zeolite Socony Mobil (H–Zsm–5) and Ion-Exchanged Zeolite: Catalytic Performance and Reusability

An efficient and sustainable method was developed for the N-formylation of primary and secondary amines using formic acid in dichloromethane at room temperature over zeolite H-ZSM-5 and ion-exchanged forms (Zn-ZSM-5, Cu-ZSM-5, Ag-ZSM-5, and Cd-ZSM-5). The catalysts were characterised by X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) surface area, ammonia temperature-programmed desorption (NH₃-TPD), and inductively coupled plasma-optical emission spectrometry (ICP-OES) analyses, revealing a regular hexagonal plate-like morphology and high surface area. H-ZSM-5 exhibited the largest surface area (248.2 m²/g) and total acidity (0.109 mmol NH₃/g), while ion exchange slightly modified these properties. The catalytic system achieved excellent yields (up to 99 %) for various amines, demonstrating high efficiency and reusability. This study highlights the potential of zeolite-based catalysts as effective, recyclable materials for N-formylation processes.