STRUCTURAL-PROPERTIES OF SOME HETEROARYL AMINES - CRYSTALLOGRAPHIC STUDIES ON 2-N-(2,4,6-TRINITROPHENYL)-PYRIDINEAMINE(I), 2-N-(2,4,6-TRINITROPHENYL)-4-METHYLTHIAZOLEAMINE(II), AND 2-N-(2,4,6-TRINITROPHENYL)-PYRIMIDINEAMINE(III)

Crystallographic properties of the title compounds are reported and inter- and intra-molecular interactions of the amino group are discussed and related to spectroscopic data. The geometry of the nitrogroups and of the 2-aminoheterocyclic moiety indicate that classical conjugation theory cannot explain the UV/vis spectra. The red shift observed on substituting H by a Me on the 2-amino group is interpreted in terms of internal charge-transfer.