화학공학소재연구정보센터
Journal of Physical Chemistry A, Vol.111, No.51, 13567-13574, 2007
Experimental and computational studies of nuclear substituted 1,1'-dimethyl-2,2'-bipyridinium tetrafluoroborates
The synthesis and spectral properties of a new 2,2'-bipyridinium ion, 1,1'-dimethyl-4,4'-(dimethylamino)2,2'-bipyridinium bis(tetrafluoroborate) are reported. Rotation of the dirnethylamino group is slow at room temperature on the 400 MHz H-1 and 100 MHz C-13 NMR time scales. Complete line shape fit of the dynamically broadened NMR spectra was used to determine the activation barriers for this process. The first complete set of UV-vis spectra for a 2,2'-bipyridinium dication and its one- and two-electron reduced products was reported. TD-DFT calculations were used to help assign the origin of the long wavelength absorptions in these species. The effect Of Substituents on the energies and conformational potential energy surfaces of all three species were also examined using the B3LYP/6-31G(d) computational method.