Development of a Rigid π‐Extended Phosphine Oxide Triphenylene‐Centered Ligand for Future Advanced Coordination Chemistry

A novel rigid π‐extended phosphine oxide ligand, 2,7‐bis(diphenylphosphoryl)triphenylene (BDPPT), was synthesized through low‐temperature lithiation of 2,7‐dibromotriphenylene followed by reaction with chlorodiphenylphosphine and subsequent oxidation with hydrogen peroxide. Purification by chromatography and recrystallization yielded BDPPT in high purity. FTIR spectra displayed characteristic aromatic and P═O absorptions at 3110–2990, 1600–1430, 1230–1180, and 1140–1030 cm −1 , with aromatic C─C stretching bands observed at 1600–1585 cm −1 and 1500–1400 cm −1 , while 1 H NMR signals appeared at 7.4–7.8, 8.4–8.5, and 9.5 ppm. A single 31 P resonance showed at 31 ppm, confirming the presence of two equivalent phosphine oxide groups. Elemental composition is C: 79.2% and H: 4.5%, found in good agreement, within acceptable analytical deviation (e.g., C: 79.0%, H: 4.6%). Powder XRD showed crystalline reflections at 11.6°, 14.0°, 15.16°, 19.17°, 22.5°, 24.33°, and 26.77°, confirming the crystalline character of the ligand. Elemental analysis matched the calculated composition for C 42 H 30 O 2 P 2 . These results confirm the successful synthesis of a structurally well‐defined phosphine oxide ligand. Owing to its rigid aromatic core and strong P═O donors, BDPPT is a promising platform for constructing photoluminescent rare‐earth and transition‐metal complexes for optoelectronic applications.