943552-01-0

5720-05-8

4408-64-4

943552-01-0

The reaction was carried out at reflux for 4 hours at 120 °C in a solvent mixture of toluene (45 L) and dimethyl sulfoxide (5 L) (9:1 by volume) using 4-tolueneboronic acid (0.68 kg, 5 mol) and N-methyliminodiacetic acid (MIDA) (0.8 kg, 5.5 mol) as the raw material. After completion of the reaction, it was slowly cooled to room temperature and toluene was removed by rotary evaporation. The residue was diluted with water and subsequently extracted three times with ethyl acetate. The organic phases were combined and washed three times with saturated saline. The organic phase was dried over anhydrous magnesium sulfate, filtered and rotary evaporated to remove the ethyl acetate. The crude product was recrystallized in petroleum ether, filtered to give a pale yellow solid and finally dried under vacuum overnight.