The Elusive Ternary Intermediates of Chiral Phosphoric Acids in Ion Pair Catalysis─Structures, Conformations, and Aggregation.

ABSTRACT: In ion-pair catalysis, the last intermediate structures prior to the stereoselective transition states are of special importance for predictive models due to the high isomerization barrier between E- and Z-substrate double bonds connecting ground and transition state energies. However, in prior experimental investigations of chiral phosphoric acids (CPA) solely the early intermediates could be investigated while the key intermediate remained elusive. In this study, the first experimental structural and conformational insights into ternary complexes with CPAs are presented using a special combination of low temperature and relaxation optimized ¹⁵N HSQC-NOESY NMR spectroscopy to enhance sensitivity. Combined NMR investigations and theoretical calculations revealed th

SUBMITTER: Franta M 

PROVIDER: S-EPMC11760147 | biostudies-literature | 2025 Jan

REPOSITORIES: biostudies-literature