AXIALLY CHIRAL SELECTORS OF C-2 SYMMETRY BOUND TO SILICA - SYNTHESIS AND HPLC-EVALUATION

Axially chiral biaryl stationary phases (CSPs) of C-2 symmetry bound t o 3-aminopropyl silica both by ionic and covalent bond were prepared. The separation effectivity of the CSPs so obtained was investigated us ing 2-acylamino alcohols and biaryl derivatives as analytes. Whereas i onically bound phases derived from biphenyl-2,2'-dicarboxylic or 2,2'- bipyridine-3,3'-dicarboxylic acids (CSP 1, 2, 3 and 4) generally exhib ited good resolving performance for 2-acylamino alcohols, they were in effective for biaryl derivatives. On the other hand, covalent CSPs sho wed poor selector properties with acylamino alcohols; the binaphthyl C SP 7 resolved some of the biaryl analytes. Phase CSP 6 was completely inactive toward all the compounds tested. Absolute configuration of 4, 4',6,6'-tetranitrobiphenyl-2,2'-dicarboxylic acid (II) has been derive d from its CD spectrum and some speculations on configuration of bipyr idine diacid IV are presented.