Enhanced fluorescence in both solution and solid state for perylene liquid crystals with six peripheral alkyl substituents on 1,6,7,12-bay positions and imides positions

The first perylene liquid crystals bearing six peripheral alkyl substituents on both 1,6,7,12-bay positions and imides positions were designed and synthesized in yields of 72–77%. The studies on their mesomorphic behaviors suggested that they possessed good ordered hexagonal columnar mesophase with low phase transition temperatures and wide ranges of mesophase temperature in comparison with their precursors with chloric groups and the similar perylene liquid crystal with 4- tert -butylphenolic groups on bay positions. Their photophysical properties revealed that they also had higher fluorescence intensities and fluorescence quantum yields than that of their precursors with chloric groups and the similar perylene liquid crystal with 4- tert -butylphenolic groups on bay positions. The good fluorescence in both solution and solid film were observed for the first time for perylene liquid crystals. This research indicated that the introduction of long p -nonylphenol units on bay position is an effect strategy to obtain perylene liquid crystal with good liquid crystalline behavior and excellent fluorescent property.