Fast and simultaneous determination of 1H–1H and 1H–19F scalar couplings in complex spin systems: Application of PSYCHE homonuclear broadband decoupling

• Published in: Magnetic resonance in chemistry Vol. 56; no. 10; pp. 1043 - 1046
• Main Authors: Kakita, Veera Mohana Rao, Rachineni, Kavitha, Hosur, Ramakrishna V.
• Format: Journal Article
• Language: English
• Published: Bognor Regis Wiley Subscription Services, Inc 01-10-2018
• Subjects: 1H–1H and 1H–19F scalar couplings; Aliasing; Broadband; broadband decoupling; Coupling (molecular); Couplings; Decoupling; Fluorination; Organic chemistry; PSYCHE; spectral aliasing; steroids
• ISSN: 0749-1581; 1097-458X
• DOI: 10.1002/mrc.4635

The present manuscript focuses on fast and simultaneous determination of 1H–1H and 1H–19F scalar couplings in fluorinated complex steroid molecules. Incorporation of broadband PSYCHE homonuclear decoupling in the indirect dimension of zero‐quantum filtered diagonal experiments (F1‐PSYCHE‐DIAG) suppresses 1H–1H scalar couplings; however, it retains 1H–19F scalar couplings (along F1 dimension) for the 19F coupled protons while preserving the pure‐shift nature for 1H resonances uncoupled to 19F. In such cases, along the direct dimensions, 1H–1H scalar coupling multiplets deconvolute and they appear as duplicated multiplets for the 19F coupled protons, which facilitates unambiguous discrimination of 19F coupled 1H chemical sites from the others. Further, as an added advantage, data acquisition has been accelerated by invoking the known ideas of spectral aliasing in the F1‐PSYCHE‐DIAG scheme and experiments demand only ~10 min of spectrometer times.