Process for separating the ortho- and para- isomers of hydroxymandelic acid or a salt thereof, the isomers thus obtained, the use of the ortho-isomer for the preparation of eddha

Abstract of WO 9414746 (A1) The invention relates to a method for separating the ortho- and para-isomers of hydroxymandelic acid or a salt thereof. For that purpose the starting material is a solid mixture of these ortho- and para-isomers in the alkali metal salt form. This mixture is extracted with a polar, aprotic, organic solvent. Then this...

Process for the preparation of polyhydroxybenzophenones

The invention relates to a process for the preparation of polyhydroxybenzophenones by treating benzoic acid or a derivative thereof with a polyhydroxybenzene or a derivative thereof in the presence of a large pore zeolite as a catalyst.