Poly(arylisocyanides) as Versatile, Enantiodiscriminating Alignment Media for Small Molecules

Lyotropic liquid crystalline (LLC) phases of amino acid derived polyarylisocyanides were employed as chiral alignment media for the measurement of residual dipolar couplings (RDCs) of small chiral organic molecules. Anisotropic samples in CDCl3 displayed quadrupolar splittings of the deuterium signal in the range of several hundreds of Hertz. The LLC phases showed excellent orienting properties for a broad range of analytes bearing various functional groups. The precise extraction of RDCs in the range of up to +/- 40 Hertz from F2-coupled HSQC spectra was possible. Additionally, the chiral environment offers the opportunity for diastereomorphous interactions with the enantiomers of chiral analytes leading to two different sets of RDCs. This differential order effect was particularly pronounced with ketones and alcohols.

Automated summary

Lyotropic liquid crystalline (LLC) phases of amino acid derived polyarylisocyanides were used as chiral alignment media for measuring residual dipolar couplings (RDCs) of small chiral organic molecules. The LLC phases exhibited excellent orienting properties for a wide range of analytes with different functional groups, allowing for accurate extraction of RDCs within the range of +/- 40 Hertz. Additionally, the chiral environment had a significant differential order effect on ketones and alcohols.