Synthesis and photophysical properties of 3,5-diaryl-2-heteroarylthiophenes

Aggregation induced emission in one easy step: pyridinium AIEgens and counter ion effect

“…Pyridine 3 displayed 3 absorption bands at 238, 292 and 322 nm (Table 1, entry 4). The absorption band of pyridine 3 at 238 nm did not change upon protonation, and remained in the range of 236-238 nm for salts 4a-f (Table 1 entries [7][8][9][10][11][12][13][14]. The absorption band of free-base 3 at 292 nm experienced slight hypsochromic shi to 281-288 nm in protonated forms 4a-c,e,f.…”

“…To demonstrate the scope and generality of the protonation approach as a means to achieve AIE and high SSL, perchlorate salt 6 of a known luminophore 5 (ref. 14) possessing a pyridine core with 3,5-diphenylthiophene substituent was prepared (Fig. 2).…”