SHighly Solvatochromic Terpyridine Compounds for Identification of Butanol Isomers

Authors：Chang, Hui; Yao, Shuangquan; Han, Wenjia; Kang, Xiena; Zhang, Li; Li, Xinping; Zhang, Zhao^*

Source：Chemical Journal of Chinese Universities, 2021, 42(3): 902-909.

DOI：10.7503/cjcu20200538

• Solvatochromism
• Terpyridine
• Butanol isomers identification
• Local excitation
• Twisted intramolecular charge transfer

N, N-Dimethyl functional group was introduced into the terpyridine molecule to realize the locally excited state luminescence of the terpyridine molecule. It was found that the polarity of the solvent induced a change in the dipole moment of terpyridine, achieving solvent-induced fluorescence discoloration from deep blue light (lambda(max)=384 nm)to yellow light (lambda(max)=558 nm). As the fluorescence of terpyridine is easily quenched by the oscillation of center dot OH group in alcohol solvent, the n-butanol, iso-butanol, sec-butanol and tert-butanol solvents with different steric hindrances make the light color of terpyridine close, while the luminous intensity difference is greater. The terpyridine is further coordinated with ZnCl2 to obtain the terpyridine-Zn (II) complex. The coordination of the metal ion Zn (II) promotes the charge transfer within the terpyridine molecule. Since the N, N-dimethyl functional group, as the electron donor can undergo plane distortion, the butanol isomers can adjust the locally excited and twisted intramolecular charge transfer of terpyridine-Zn (II), and then realize the adjustment of its light color in butanol isomer solvent. Terpyridine and terpyridine-Zn (II) have good solvent-induced fluorescence discoloration properties, and can be used to identify four butanol isomers.

• Institution
  广西大学; 陕西科技大学