Effects of molecular flexibility/rigidity on the AIE/AIEE properties of aromatic thiols substituted 1,8-naphthalimides

摘要

Sulphur linked six 1,8-naphthalimide-phenyl/naphthalene conjugates (NATs 1-6), were designed, synthesized and fully characterized by H-1 NMR, C-13 NMR and mass spectroscopy. The effects of aromatic substituent and molecular rigidity in NATs 1-6 on the absorption, fluorescence and aggregation induced emission (AIE)/aggregation induced emission enhancement (AIEE) were explored. NATs 1-5 and 6 were shown AIE and AIEE behavior in THF: water mixtures respectively. Molecular flexibility provided by the thioether linkage override steric hindrance in the 2,6-dimethylbenzenethiol-naphthalimide conjugate. The formation of nano-aggregates in THF: water (1:9 v/v) solution of NATs 1-6 were further confirmed by dynamic light scattering and transmission electron microscope.