Bond shift kinetics in cyclohyphen;octatetraene by dynamic NMR in liquid crystalline solvents

摘要

A complete line shape analysis of the dynamic NMR spectra of cyclohyphen;octatetraene dissolved in nematic liquid crystalline solvents is presented. The analysis involves simulation of the dynamic NMR spectra in the presence of the bond shift reaction. This is performed using a newly developed group theoretical method. Comparison of the simulated and experimental spectra yield the following kinetic parameters for the bond shift process in cyclohyphen;octatetraene: 1/tgr; (0thinsp;deg;C) = 2.3times;102sminus;1; Dgr;E= 10.62 kcal/mol; Dgr;Hne;= 10.0 kcal/mol; Dgr;Sne;= minus;9.7 e.u.