The Synthesis and Properties of Spirophenanthrene.

Motivated by the success of 9,9'-spirobifluorene ( SBF ) in optoelectronic materials, we synthesized a novel spiro compound, spirophenanthrene ( SP ). Incorporating a phenanthrene unit as the core, we aimed to leverage the π-conjugation of SPs to surpass the limitations of SBF . Experimental and theoretical studies revealed significant advantages over SBF , including red-shifted wavelengths, tunable LUMO energy levels, and enhanced thermal stability. These advantages suggest the potential of SPs as versatile building blocks for diverse optoelectronic devices.