Piperidine ring systems are key structural elements in a vast array of natural products, as well as in a large class of biologically active compounds. They are often embedded within scaffolds recognized as privileged structures by medicinal chemists [1]. The biological importance of this ring system places high value on short and versatile synthetic routes to substituted piperidines [2], and therefore makes rapid structural elucidation of these compounds crucial. Typically, these elucidations require acquiring a range of standard NMR experiments, such as COSY, HSQC, and NOESY, which makes the process quite time-consuming. In this challenge, we will attempt to distinguish cis/trans isomers of two 3,4-disubstituted piperidines (Fig. 1) from their heteronuclear (1H-13C) single quantum coherence (HSQC) NMR spectra.

(4-Phenylpiperidin-3-yl)methanol