C13 Nuclear Magnetic Resonance Spectroscopy. III. Iodobenzene and Methyliodobenzenes

Publisher Website
Google Scholar
Abstract
The C13nuclear magnetic resonance spectra of iodobenzene and six methyliodobenzenes have been obtained and complete assignments have been made. Large deviations from additivity of the shieldings of ring carbon atoms ortho to either the methyl group or the iodine atom are found when the two substituents are ortho to one another, and there is some evidence for a specific interaction with a para methyl group. Long‐range magnetic anisotropyeffects are believed to be too small to account for the observed anomalously high shielding of carbon bonded to iodine and the unusually low shieldings of carbon nuclei two or three bonds distant.