Abstract: Colored complexes of bidentate Lewis acids R[OB(C6F5)2]2 (R = p-C6H4, p-C6F4) with pyrazine have been synthesized. A mass spectrometric study of the obtained complexes was carried out, as a result of which it was established that upon heating, dissociation processes occur with a sequential transition into pyrazine and Lewis acid vapor. Using the method of diffuse reflectance spectroscopy in the visible and ultraviolet regions, the color of the compounds was characterized and a mechanism for its appearance was proposed, which consists in the presence of π–π interactions in the solid phase.