Dynamic Structure and Chirality Effects on 1H and 13C NMR Chemical Shifts for Aerosol OT in Reversed Micelles Assisted by NOESY, ROESY, and 13CT1 Studies

Abstract

The 13C NMR spin−lattice relaxation time (T1) and 13C{1H} NOE of the individual carbon atoms of each 2-ethylhexyl chain in an aerosol OT (AOT) molecule have been investigated in the reversed micellar state, and the segmental mobility of each 2-ethylhexyl chain has been discussed independently in connection with the chirality effect on the 13C chemical shifts. Measurements of the NOESY and ROESY spectra of an AOT molecule and cross-peak assignments have been made. In particular, for the ROESY spectrum, the cross-peaks arising from the dipole−dipole interaction have been used to discuss successfully the spatial proximity of the two 2-ethylhexyl chains. It has also been found that the carbon atom having the larger 1/ values provides larger secondary splitting of the 13C chemical shift. Furthermore, the dipole−dipole interaction between the H3 or H3‘ protons and other specific protons has been found to be strongly dependent on the diastereoisomers. Selective NOE measurements were also made, and the proximity ...