| Summary: | 碩士 === 國立中興大學 === 化學系所 === 100 === The NMR spectroscopic investigation on the iminium ion pairs of metal complexes 5-7, 10, 11 in CDCl3 was reported. An equilibrium between ion pairs (or dipolar canonical form II) and covalent species (canonical form I) exists in CDCl3. To develop the correlations between δ13C [C(3)], δ1H [H(3)] and ion pairs (canonical form II) in 5-7, 10, 11, this work also thoroughly examines the 13C and 1H NMR of N+ = CH(Ar) fragment on seven metal complexes of 2-N substituted N-confused porphyrin. According to these results, the 13C [C(3)] and 1H [H(3)] chemical shifts of the N+ = CH(Ar) fragment at 20°C in CDCl3 are separately located at 152.6 ± 0.5 and 8.30 ± 0.15 ppm for the iminium ion, which is in a ion pairs form II for complexes 5-7, 10, 11 and at 121.1 ± 0.1 ppm and 6.35 ± 0.01 ppm of the N-CH(Ar) group, which is in a covalent form I for complexes 4, 8. X-ray diffraction data indicate N(2)-C(3) = 1.315 ± 0.011 A for ion pairs species of 5-7, 10-13 and N(2)-C(3) = 1.331 ± 0.008 A for covalent species of 4, 8.
|
|---|
