A novel thiazolothiazole-bridged imidazole derivative(1) was found to exhibit blue fluorescence in gaseous state or in methanol and yellow fluorescence in solid state. The N-alkylation of imidazole subunit(s) in 1 usi...A novel thiazolothiazole-bridged imidazole derivative(1) was found to exhibit blue fluorescence in gaseous state or in methanol and yellow fluorescence in solid state. The N-alkylation of imidazole subunit(s) in 1 using n-propyl iodide generated unsymmetrically or symmetrically alkylated thiazolothiazolebridged imidazolium salts with good water solubility and remarkably strong emission in solution. Furthermore, the replacement of iodide counter-anion by triflate or bis(trifluoromethane sulfonyl)imide achieved remarkably strong emission in solid state and in solution as well as good water solubility. The strong fluorescence of dicationic salts with triflate and NTf_(2)^(-)counter-anions in solid state can be ascribed to their twisted and rigid structures induced by interionic C-H···F hydrogen bonding.展开更多
基金National Natural Science Foundation of China(Nos.U20041101,21772034,U1704251)the Top-notch Personnel Fund of Henan Agricultural University(No.30500418)for financial support。
文摘A novel thiazolothiazole-bridged imidazole derivative(1) was found to exhibit blue fluorescence in gaseous state or in methanol and yellow fluorescence in solid state. The N-alkylation of imidazole subunit(s) in 1 using n-propyl iodide generated unsymmetrically or symmetrically alkylated thiazolothiazolebridged imidazolium salts with good water solubility and remarkably strong emission in solution. Furthermore, the replacement of iodide counter-anion by triflate or bis(trifluoromethane sulfonyl)imide achieved remarkably strong emission in solid state and in solution as well as good water solubility. The strong fluorescence of dicationic salts with triflate and NTf_(2)^(-)counter-anions in solid state can be ascribed to their twisted and rigid structures induced by interionic C-H···F hydrogen bonding.
