A novel eco-friendly and highly efficient ionic liquid catalyst derived from valine and immobilized on nano magnetic cellulose for the epoxidation of olefins with excellent recyclability

Abstract

Developing catalysts that combine high efficiency with recyclability is key to achieving sustainable organic synthesis. To this end, a novel [AcIm-Va]Br@Py-ImineCr@MCS complex was synthesized using the amino acid valine and subsequently immobilized on magnetic cellulose, forming a heterogeneous catalytic system. Physicochemical characterization of the catalyst was conducted using Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and vibrating sample magnetometry (VSM). The resulting ionic liquid-based catalyst demonstrated outstanding selectivity toward epoxide formation and achieved a remarkable catalytic efficiency of 98% in the epoxidation of diverse aromatic and aliphatic olefins. Maximum catalytic efficiency was achieved under mild and sustainable conditions, 50 ℃ with only 0.16 mol% Cr and 1.5 mmol H2O2, employing water as an eco-friendly solvent and hydrogen peroxide as a clean oxidant. The system’s significant environmental and practical advantages arise from its heterogeneous nature, straightforward magnetic separation, excellent reusability, operation under mild conditions without high temperatures or additives, and minimal catalyst loading requirements, establishing it as a highly effective and sustainable epoxidation methodology. This strategy presents a sustainable and highly efficient route for olefin epoxidation.