Mechanochemical Synthesis of Aryldiazenyl‐2‐diindolylmethylphenols Using Fe ₃ O ₄ @SiPr@Gabapentin Nanocomposite and Study of Their Antioxidant Activity

Abstract A novel, environmentally friendly, and solvent‐free approach utilizing mechanochemical method is presented for the synthesis of aryldiazenyl‐2‐diindolylmethylphenol derivatives. This method involves a three‐component reaction between aryldiazenylaldehydes and two equivalents of various indoles, employing a recyclable magnetic nanocatalyst, specifically Fe 3 O 4 @SiPr@gabapentin magnetic nanocomposites (MNCs). The characterization of the structure and morphology of the Fe 3 O 4 @SiPr@gabapentin MNCs was conducted using several techniques, including Fourier transform‐infrared spectroscopy (FT‐IR), energy dispersive X‐ray spectroscopy (EDS), X‐ray diffraction (XRD), zeta potential measurements, field emission scanning electron microscopy (FE‐SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and a vibrating sample magnetometer (VSM). The structural confirmation of the synthesized aryldiazenyl‐2‐diindolylmethylphenol compounds was achieved through FT‐IR, 1 H NMR, 13 C NMR spectrometry, and elemental analysis. Also, after synthesizing these heterocyclic compounds, their antioxidant activities were studied using the 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH).