Molecular Pharmacology, Vol 13, 892-900, Copyright © 1977 by the American Society for Pharmacology and Experimental Therapeutics

Electron Densities in Neuroleptics by X-ray Photoelectron Spectroscopy, ¹³C Nuclear Magnetic Resonance, and Quantum Calculations on Model Compounds

¹ Laboratoire de Spectroscopie Electronique, Facultés Universitaires Notre-Dame de la Paix, B-5000 Namur, Belgium
² Laboratoire de Chimie Pharmaceutique, Université Catholique de Louvain, B-1200 Bruxelles, Belgium
³ Research Laboratories, Janssen Pharmaceutica, B-2340 Beerse, Belgium

Nitrogen is electron binding energies of a series of neuroleptics in the solid state have been obtained by X-ray photoelectron spectroscopy. The ¹³C NMR data give a good correlation between the charges on the carbonyl carbons and the corresponding chemical shifts, thereby providing evidence for the internal consistency of the CNDO/2 (complete neglect of differential overlap) charge densities obtained for the N-ethyl analogues. An analogy between X-ray photoelectron spectroscopic results in the gas phase and in the solid state suggests that the nitrogen 1s shifts measured in the solid state can be related to the proton affinity of amines.