Isobenzopyryliumsalts: VII—13C n.m.r. shifts of 1-arylisobenzopyrylium salts and correlation with Hammett parameters

The signal identifications of isobenzopyrylium salts has been achieved on the basis of proton broad-band and off-resonance decoupled ¹³C n.m.r. spectra of twelve different 1-arylisobenzopyrylium salts and eight model compounds. From the ¹³C shifts valuable information about pK values, the aromatic character and the conjugative effects of isobenzopyrylium salts was obtained.