The general procedure for the synthesis of 2-phenoxyphenylboronic acid from triisopropyl borate and 2-bromobiphenyl ether was as follows: 1-bromo-2-phenoxybenzene (0.018 mmol) was dissolved in 100 mL of anhydrous THF and added to an undried 500 mL triple-necked flask. The reaction system was cooled to -78 °C under nitrogen protection and maintained at this temperature for 30 min. Subsequently, n-butyllithium (0.027 mmol) was slowly added dropwise, and after the drop was completed, the reaction was maintained at -78 °C for 3 hours. Next, triisopropyl borate (0.02 mmol) was added dropwise slowly, and after the dropwise addition was completed, the reaction was continued at -78 °C for 2 hours. After that, the reaction was slowly warmed up to room temperature and reacted overnight. The progress of the reaction was monitored by TLC and after confirming the completion of the reaction, the reaction solution was quenched slowly by the addition of water, followed by extraction to dryness to give 2-phenoxyphenylboronic acid (B-1) (0.0144 mmol) in 80% yield. Mass spectral data: 214.06.
