NMR Spectra of Glycine Isotopomers in Anisotropic Media: Subtle Chiral Interactions.

Abstract

NMR spectra of deuterated glycine-2-(13)C revealed interactions between chiral anisotropic gelatin and κ-carrageenan gels and the prochiral and chiral isotopomers. The (1)H, (2)H and (13)C NMR spectra of mixtures of racemic mono- and prochiral bis-deuterated glycine-2-(13)C were resolved and well simulated using distinct dipolar coupling constants DCαH and DCαD for the enantiomers and also for the -(13)CαD2- group (DC,DA, and DC,DB). The orientation of the proton or deuteron on the (13)Cα-atom of glycine was assigned by analogy with alanine and lactate assuming that the molecular orientation of glycine isotopomers is the same. The assignment of the prochiral sites was derived from chiral analogues.