p-Aminobenzoesure-2-ethylhexylester

16397-70-9

26218-04-2

The general procedure for the synthesis of 2-ethylhexyl 4-aminobenzoate from 2-ethylhexyl 4-nitrobenzoate was as follows: in a three-necked flask equipped with a stirrer, 920 mL of methanol-water solution (V methanol: V water = 5:1), 48.15 g (1.8 mol) of ammonium chloride, 33.60 g (1.2 mol) of reduced iron powder and 55.87 g (0.20 mol) 2-ethylhexyl 4-nitrobenzoate. The mixture was heated to reflux and the reaction was maintained for 16-17 hours. The progress of the reaction was monitored by thin layer chromatography (TLC) during the reaction. Upon completion of the reaction, the reaction mixture was filtered while hot and the diatomaceous earth filter cake was washed twice with methanol. The filtrate and washings were combined and concentrated under reduced pressure to obtain the crude product. The crude product was dissolved in 200 mL of water, the pH was adjusted to 7-8 with saturated sodium carbonate solution, and then extracted twice with 200 mL of dichloromethane. The organic phases were combined and dried by adding anhydrous magnesium sulfate for 3 hours. After drying, the magnesium sulfate was removed by filtration, and the filtrate was concentrated under reduced pressure to obtain the intermediate 2-ethylhexyl 4-aminobenzoate as a light yellow solid with 88.7% yield.