Importance of molecular symmetry for enantiomeric excess recognition by NMR.
Chem Commun (Camb)
; 58(35): 5423-5426, 2022 Apr 28.
Article
en En
| MEDLINE
| ID: mdl-35416216
ABSTRACT
Recently prochiral solvating agents (pro-CSA) came under the spotlight for the detection of enantiopurity by NMR. Chemical shift non-equivalency in achiral hosts introduced by the presence of chiral guests yields observable resonance signal splitting (Δδ) correlating to the enantiomeric excess (e.e.). In this work, symmetry is our lens to explain porphyrin-based supramolecular receptor activity in a chiral environment. Based on extensive NMR analyses of the atropisomeric receptors, the host symmetry is shown to be affected by porphyrin nonplanarity and further desymmetrized in the presence of a chiral guest. As such, the exposed porphyrin inner core (N-H), with its strong hydrogen bond abilities, for the first time, has been exploited in enantiomeric composition analysis. Our approach in e.e. detection by N-H signals appearing in a previously underutilized region of the spectrum (below 0 ppm) shows chemical shift splitting (Δδ) three times more sensitive to enantiomeric compositions than previously reported systems.
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1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Porfirinas
/
Imagen por Resonancia Magnética
Idioma:
En
Revista:
Chem Commun (Camb)
Asunto de la revista:
QUIMICA
Año:
2022
Tipo del documento:
Article
País de afiliación:
Irlanda