2.3. Procedure of the Suzuki-Miyaura Cross-Coupling Reactions

The catalytic test reactions were carried out in a 10 cm³ glass reactor immersed into a preheated oil bath. Iodobenzene (1.0 mmol), phenylboronic acid (1.2 mmol), potassium carbonate (2.5 mmol) and Ni NPs (0.15 mmol) were mixed in 4 cm³ of various solvents (DMF, DMSO, toluene), and 1 cm³ of distilled water was added to increase the solubility of the K₂CO₃ base. The reaction was conducted under reflux, and the reaction time was varied from 1 to 24 h. The reaction was followed primarily by thin-layer chromatography (hexane:ethylacetate 19:1), and at the end of the reaction, the solid catalysts were filtered, and the clear liquids were analysed on a Hewlett-Packard 5890 gas chromatograph (Hewlett-Paclard, Budapest, Hungary) equipped with 50 m × 0.2 mm × 0.33 µm HP-FFAP (nitroterephthalic acid modified polyethylene glycol) column and flame ionization detector. The chromatographic peaks were identified using commercial calibration standards.