Syntheses, spectroscopy, and crystal structures of 3-(4-bromo­phen­yl)-1,5-di­phenyl­formazan and the 3-(4-bromo­phen­yl)-1,5-di­phenyl­verdazyl radical and the crystal structure of the by-product 5-anilino-3-(4-bromo­phen­yl)-1-phenyl-1H-1,2,4-triazole

The title compounds, C(19)H(15)BrN(4), C(20)H(16)BrN(4) and C(20)H(15)BrN(4), are nitro­gen-rich organic compounds that are related by their synthesis. The verdazyl radical, in which stacking leads to anti­ferromagnetic inter­actions, was reported previously [Iwase et al. (2013 ▸). Phys. Rev. B, 88, 184431]. For this compound, improved structural data and spectroscopic data are presented. The other two compounds have been crystallized for the first time and form stacks of dimers, roughly along the a-axis direction of the crystal. The formazan mol­ecule shows signs of rapid intra­molecular H-atom exchange typical for this class of compounds and spectroscopic data are provided in addition to the crystal structure. The triazole compound appears to be a side-product of the verdazyl synthesis.