Inclusion of cresols by β cyclodextrin in DHO has been investigated by 1H NMR spectra. Although chemical shifts of the same proton are different in the cavity of empty and enclosed β cyclodextrin, only a time average peak has been detected for a proton in the spectra. The value of chemical shift corresponds to enclosed degree of cresol by β cyclodextrin. The average structure of inclusion has been determined based on 1H NMR data, it describes dynamic depth of cresol in the cavity of β cyclodextrin.
The title compound was obtained as a by product in a contraction reaction by using DIC as a coupling reagent. X ray diffraction shows the title compound is a pyrrolinenitroxide radical urea. Two crystallographically independent molecules possess different conformations but the identical bond distances and angles. Based on the molecular structure a possible reaction mechanism is proposed for the reaction of DIC and carboxylic acid.
