55453-89-9

The general procedure for the synthesis of 2-[(4-carboxymethylphenoxy)methyl]benzoic acid using the compound (CAS:1009378-92-0) as starting material was as follows: intermediate I (3.2 kg, 10.2 mol) and TEBA (34 g) were dissolved in ethanol and potassium hydroxide (1.2 kg, 21.4 mol) was added with stirring. The reaction mixture was heated to reflux for 3 hours. After completion of the reaction, the ethanol was removed by evaporation. Water (20 L) was added to the residue to dissolve it, followed by acidification with concentrated hydrochloric acid to pH 1-2, when a large amount of light yellow solid precipitated. The solid was collected by filtration and the filter cake was washed with water to neutral and dried to give Intermediate II (2.42 kg) as a light yellow solid in 83.1% yield.

[1] Patent: CN104262318, 2016, B. Location in patent: Paragraph 0053; 0054
[2] Patent: EP2058294, 2009, A1. Location in patent: Page/Page column 8-9
[3] Patent: EP2072507, 2009, A1. Location in patent: Page/Page column 10