|Name||Ms. Sandra Khalife|
|Organization or Institution||University of South Florida|
Emissive Pyridinium Salts Constructed through Restriction of the Intramolecular Rotation of Tetraphenylethylene
Sandra Khalife, Guangqiang Yin, Xiaopeng Li
Department of Chemistry, University of South Florida, Tampa FL 33620, USA
During the past few years, pyridinium salts chemistry has been developed as a powerful modular synthesis strategy to prepare complicated molecules. Encouraged by the power and versatility of this approach, herein, we successfully performed synthesis of four-armed pyridinium salts based on tetraphenylethylene (TPE) using the combination of 4,4',4'',4'''-(ethene-1,1,2,2-tetrayl)tetraaniline and pyrylium salts. The highly efficient condensation reaction between primary amino precursor and pyrylium salts enabled the synthesis of multi-armed pyridinium salts in high yields. The restriction of the intramolecular rotation (RIR) of TPE, leads to emission in both solution and aggregation states. Furthermore, we extended the arms of pyridinium salts to introduce more RIR, thus those compounds exhibited tunable emissive properties. Those pyridinium salts were fully characterized by electrospray ionization-mass spectrometry (ESI-MS), multinuclear NMR (1H and 13C) analysis, X-ray crystallography, ultraviolet-visible and fluorescence spectroscopy.