The present invention relates to a new process for the resolution of mandelic acid derivatives from racemic mandelic acid derivative mixtures by salt formation with chiral base cyclic amides; to the resolved mandelic acid cyclic amide salts (see, for example, formula IIa), as well as certain other metal and amine salts of the mandelic acid derivatives, and to the use of the resolved mandelic acid derivatives as intermediates suitable for large-scale manufacturing of, for example, pharmaceutical compounds; Formula IIa, wherein R is selected from CHF2, H, C1-6 Alkyl, CH2F, CHCl2 and CClF2; and wherein n is 0, 1 or 2; R1 is H or C1-6 Alkyl and X is H, halo or C1-6 Alkyl.