Precision X-ray Diffraction Study of the Secondary Interactions in the Crystal of 1-Dimethylcarbamoyl-8-Dimethylaminonaphthalene

Abstract

X-ray diffraction method has been used to study the structure and electron density distribution in the crystal of 1-dimethylcarbamoyl-8-dimethylaminonaphthalene. Attractive interaction between a nucleophilic nitrogen atom and an electrophilic carbon atom has been established. These atoms are at a distance of 2.71 Å which is much less than the sum of the Van der Waals radii (3.25 Å). A number of specific features in the deformation electron density maps are accounted for by this interaction. Comparative analysis of the structural features of the compound studied (along with theoretical calculations by MMP2 and MNDO methods) and a number of other naphthalene perisubstituted derivatives confirms the presence of the attractive interaction.

Key Words:

• X-ray diffraction
• electron density distribution