Impact of the substitution pattern of the acceptor on the properties of the bis(trifluoromethyl)phenyl disubstituted aromatic diamines

New aromatic diamines with bis(trifluoromethyl)phenyl substituents were synthesized and investigated. Theoretical and experimental results revealed that compounds containing 2,5-bis(trifluoromethyl)benzene moiety exhibit interplay between inductive and mesomeric effects opening new possibilities in the field of organic optoelectronics. Furthermore, the CF₃ group at ortho position leads to the closer packing of molecules in the single crystal as well as in the amorphous state. As a result, CF₃ group decreases the ionization potential and enhance the hole mobilities of the synthesized compounds containing 2,5-bis(trifluoromethyl)benzene moieties as compared to their counterparts containing 3,5-bis(trifluoromethyl)benzene moieties.