Pure shift NMR by PSYCHE
Unusual double for NMR researcher.
Mohammadali Foroozandeh, of the NMR methodology group, has scored an unusual double with communications in both Angewandte Chemie (DOI: 10.1002/anie.201404111) and JACS (DOI: 10.1021/ja507201t) attracting attention in recent months, the former in Chemical and Engineering News (Chem. Eng. News 92(23), 8) and SpectroscopyNow and the latter as an ACS Spotlight (currently in preparation). In both papers the work involves a new NMR pulse sequence element, PSYCHE (Pure Shift Yielded by Chirp Excitation) that allows the effects of spin-spin couplings to be refocused, and hence proton spectra to be measured without multiplet structure. PSYCHE is unusual among pure shift NMR methods in being surprisingly tolerant of strong coupling, allowing clean simple spectra to be obtained even for complex spin systems such as steroids. The two communications illustrate the use of PSYCHE in 1D and 2D NMR respectively, in each case using the spectrum of estradiol as an example.