Syntheses, crystal structures, luminescence, Hirshfeld surface analyses and thermal properties of biphenyl carbazole derivatives

Abstract Two biphenyl carbazole-based derivative, namely, 9-(4′‑bromo-[1,1′-biphenyl]-4-yl)-9H-carbazole (1) and 9-(4′‑bromo-[1,1′-biphenyl]-4-yl)-3,6-diiodo-9H-carbazole (2) have been obtained. Compound 2 was prepared through the iodination on 9-(4′‑bromo-[1,1′-biphenyl]-4-yl)-9H-carbazole (1). Two compounds were characterized by FI-IR, UV–Vis spectra, elemental analyses and single-crystal X-ray diffraction. Compound 1 crystallizes in the formation of the space group P21/n. There exist C H⋯π stacking interactions among aromatic rings. Compound 2 belongs to the space group P-1, and it occurs intermolecular C H⋯π and π⋯π packing interactions among aromatic rings. Thermogravimetric analyses (TGA) of two compounds exhibit high thermal stabilities, in which the decomposition temperature for 1 and 2 are 298 and 368 °C, respectively. Additionally, the maximal peaks of compounds 1 and 2 are 386 and 410 nm, respectively. The Hirshfeld analyses reveal that the intermolecular contacts of Br∙∙∙C, I∙∙∙C and C∙∙∙C are responsible for the maximal bands.