Silicone phthalocyanine (SiPc) and naphthalocyanine (SiNc) containing two n-dodecyloxy axial ligands were synthesized and their NMR spectra were recorded. The effect of the Pc or Nc ring current on their axial ligands was compared between the two systems by using chemical shifts. The ring current effect was larger for Pc in the close vicinity of the molecular center, but at a higher point (about 10 or more carbon atoms) that by the Nc ring becomes stronger. The effect was calculated by computer on the basis of the loop-current effect of π- electrons. Thus, a five- or nine-loop model was used for the Pc or Nc ring, respectively. In close accord with the above experimental results, calculations indicate that the loop-current effect of Pc is larger in the close vicinity of the molecular center but at a distance of more than c. 5 Å from the molecular center that of the Nc ring becomes larger.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Inorganic Chemistry
- Materials Chemistry