Abstract
Seven rubrene analogues with varying substituents including triisopropylsilyl acetylene (TIPSA), phenyl acetylene, phenyl, and thienyl substituents were studied for photo-oxidation stability as a function of substituents. Stability ordering was determined via half-life value calculations by observing the depletion of absorption peaks in the UV-Vis spectrum. Ordering of stability did not trend with electronic structure, however, thienyl substituents was deemed to be the most stabilizing against photo-oxidation. Additionally, crystal structures of obtained endoperoxide products reveal a consistent regioselective site for oxidation across ethynl flanked rings, where applicable. Quantum calculations results using DLPNO−CCSD(T) methods reveal a preferred concerted oxidation pathway for all analogues studied and agrees with experimental results. Demonstration from this work addresses the photo-oxidative resistance as a function of substituents effects in rubrene, enabling the rational design for stable linearly annelated polycyclic aromatic hydrocarbons.