An Examination of Factors Influencing Small Proton Chemical Shift Differences in Nitrogen-Substituted Monodeuterated Methyl Groups

Monodeuterated methyl groups have previously been demonstrated to provide access to long-lived nuclear spin states. This is possible when the CH2D rotamers have sufficiently different populations and the local environment is chiral, which foments a non-negligible isotropic chemical shift difference between the two CH2D protons. In this article, the focus is on the N-CH2D group of N-CH2D-2-methylpiperidine and other suitable CH2D-piperidine derivatives. We used a combined experimental and computational approach to investigate how rotameric symmetry breaking leads to a H-1 CH2D chemical shift difference that can subsequently be tuned by a variety of factors such as temperature, acidity and 2-substituted molecular groups.

Automated summary

This article focuses on investigating how the breaking of rotameric symmetry in N-CH2D-2-methylpiperidine and other suitable CH2D-piperidine derivatives leads to a chemical shift difference, which can be tuned by factors such as temperature, acidity, and 2-substituted molecular groups. The study utilized a combination of experimental and computational approaches to explore this phenomenon.