Premium
19 F DOSY NMR analysis for spin systems with n J FF couplings
Author(s) -
Dal Poggetto Guilherme,
Favaro Denize C.,
Nilsson Mathias,
Morris Gareth A.,
Tormena Cláudio F.
Publication year - 2014
Publication title -
magnetic resonance in chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.483
H-Index - 72
eISSN - 1097-458X
pISSN - 0749-1581
DOI - 10.1002/mrc.4047
Subject(s) - chemistry , fluorine , pulse sequence , fluorine 19 nmr , coupling constant , coupling (piping) , analytical chemistry (journal) , spin (aerodynamics) , computational chemistry , nuclear magnetic resonance spectroscopy , combinatorial chemistry , stereochemistry , nuclear magnetic resonance , organic chemistry , thermodynamics , mechanical engineering , physics , particle physics , engineering
NMR is a powerful method for identification and quantification of drug components and contaminations. These problems present themselves as mixtures, and here, one of the most powerful tools is DOSY. DOSY works best when there is no spectral overlap between components, so drugs containing fluorine substituents are well‐suited for DOSY analysis as 19 F spectra are typically very sparse. Here, we demonstrate the use of a modified 19 F DOSY experiment (on the basis of the Oneshot sequences) for various fluorinated benzenes. For compounds with significant n J FF coupling constants, as is common, the undesirable J ‐modulation can be efficiently suppressed using the Oneshot45 pulse sequence. This investigation highlights 19 F DOSY as a valuable and robust method for analysis of molecular systems containing fluorine atoms even where there are large fluorine–fluorine couplings. Copyright © 2014 John Wiley & Sons, Ltd.