Nuclear resonance spectrum of ortho bromoaniline

The changes produced in the nuclear magnetic resonance spectrum of the ring protons of o-bromoaniline by the addition of acetone are found to be associated almost entirely with the decreased shielding of the proton ortho to the amino group. A series of spectra obtained with different amounts of acetone enables the spectral lines due to the individual protons to be identified and approximate values of the chemical shift and spin-spin coupling parameters to be deduced. These are used as a basis for a series of calculated spectra which progressively yield more accurate values of the parameters and finally a close agreement with the experimental spectrum. The dependence of the varying chemical shift upon acetone concentration is measured and discussed.