| 초록 |
We investigate a series of π-conjugated aryltriene chromophores having electron donor groups such as pyrrolic and phenyl groups, which exhibit twisted intramolecular charge transfer excited states for molecular rotor. The aryltriene chromophores having methylpyrrolic and phenylpyrrolic group exhibit a large change of molecular fluorescence emission intensity of up to 30 times in various viscous medium. It is attributed to change of free rotation in pyrrolic groups. Two pyrrolic-triene chromophores, 2-(5,5-dimethyl-3-(2-(1-methyl-1H-pyrrol-2-yl)vinyl)cyclohex-2-en-1-ylidene)malononitrile (MP) and 2-(5,5-dimethyl-3-(2-(1-phenyl-1H-pyrrol-2-yl)vinyl)cyclohex-2-en-1-ylidene)malononitrile (PP) exhibit similar degree of intramolecular twisting. While, the degree of change of phenylaryltriene chromophore having dimethylamino group in fluorescence emission was much smaller (＜ 2 time) than pyrrolic-triene chromophores. |
