METHOD OF REMOVING THE TRIPHENYLMETHANE PROTECTION GROUP

摘要

The present invention relates to a method of removing triphenylmethane protection group. The method for preparing biphenyl benzoic acid derivatives of the present invention is economically advantageous and very excellent in the aspect of improving process in that: process safety is secured by using acidic ion exchange resin in the presence of organic solvent instead of using highly corrosive acid; the reaction takes much less time than do the conventional reactions which use only anhydrous methanol and few sub-reaction does occur; and the ion-exchange resin of the present invention is excellent for mass-processing because the resin can be collected and recycled only by filtration after being used.