3-(4-bromophenyl)-5-(4-dimethylaminophenyl)-1-phenyl-2-pyrazoline:: X-ray and density functional theory (DFT) studies

In the crystal structure of the title compound, C23H22BrN3, a strong conjugation of the pyrazoline chromophore with the aromatic rings at positions I and 3 is observed, as well as a significant shift in the synclinal -> synperiplanar direction. The absolute structure was unequivocally determined. In the absence of clasical hydrogen-bond donors, the structure is stabilized by weak C-H center dot center dot center dot pi interactions. This paper also reports the electronic structure of the title compound using NBO (natural bond order) analysis. The contributions of lone pairs to the relevant bonds were revealed.