Characterization of a chiral stationary phase by HR/MAS NMR spectroscopy and investigation of enantioselective interaction with chiral ligates by transferred NOE.

The surface chemistry of a chiral stationary phase (CSP) with a (tert-butyl carbamoyl) quinine selector immobilized on thiol-modified silica has been characterized by (1)H HR/MAS NMR and (29)Si CP/MAS NMR spectroscopy. The mostly well-resolved (1)H signals could be assigned to stem from the surface-bound selector and the latter suggested a bi- and trifunctional silane linkage. Suspended-state NMR spectroscopy thus proved a well-characterized surface chemistry as proposed.

Comparisons of the interactions between two analytes and two structurally similar chiral stationary phases using high-performance liquid chromatography, suspended-state high-resolution magic angle spinning nuclear magnetic resonance and solid-state nuclear magnetic resonance spectroscopy.

A study of the retention behaviour of the enantiomers (R)- and (S)-1,1'-binaphthyl-2,2'-diol as well as (+) and t-)-O,O'-dibenzoyl-tartaric acid was performed using the two chiral stationary phases (CSPs) Kromasil-DMB and Kromasil-TBB. Detailed information about the interactions between the analytes and the two CSPs was obtained from suspended-state HR/MAS transferred NOESY NMR experiments as well as suspended-state HR/MAS 1H NMR titration experiments. Good correlation between the suspended-state HR/MAS NMR experiments and the corresponding HPLC experiments was obtained.