Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Aromatic region of the 1H NMR spectra of 3 at different temperatures (500 MHz, d6 ‐DMSO). At room temperature, three species are observable. Above 70 °C, the broad resonances of 3‐A have disappeared and only 3‐M and 3‐D remain. At the highest temperature, 3‐M dominates the spectrum. As the 25 °C spectrum after the temperature elevation (top spectrum) is equal to the initial 25 °C spectrum before the VT NMR experiment (bottom spectrum), the observed processes are reversible.
