TY - JOUR
T1 - Fluorescence sensing of anions based on inhibition of excited-state intramolecular proton transfer
AU - Wu, Yunkou
AU - Peng, Xiaojun
AU - Fan, Jiangli
AU - Gao, Shang
AU - Tian, Maozhong
AU - Zhao, Jianzhang
AU - Sun, Shiguo
PY - 2007/1/5
Y1 - 2007/1/5
N2 - Condensation of 2-(2′-aminophenyl)benzoxazole with p-toluenesulfonyl chloride and phenyl isocyanate yields two new anion sensors (TABO and PUBO), which can undergo excited-state intramolecular proton transfer (ESIPT) upon excitation. For the acid receptor TABO, the ESIPT process can be readily disturbed by basic anions such as F-, CH3COO-, and H2PO4- by deprotonating the sulfonamide unit, whereas in the case of PUBO, a good hydrogen-bonding donor, the ESIPT process is inhibited either by the fluoride-induced deprotonation of the urea unit or by the formation of a strong CH3COO--urea intermolecular hydrogen bond complex, and these two types of inhibition mechanisms consequently result in different ratiometric responses. But other anions with less hydrogen-bonding acceptor abilities cannot inhibit the ESIPT, Interestingly, the different inhibition abilities of F-, CH 3COO-, and H2PO4- produce different spectral behaviors in PUBO, so this new sensor successfully distinguishes the subtle difference in these three anionic substrates of similar basicity and surface charge density.
AB - Condensation of 2-(2′-aminophenyl)benzoxazole with p-toluenesulfonyl chloride and phenyl isocyanate yields two new anion sensors (TABO and PUBO), which can undergo excited-state intramolecular proton transfer (ESIPT) upon excitation. For the acid receptor TABO, the ESIPT process can be readily disturbed by basic anions such as F-, CH3COO-, and H2PO4- by deprotonating the sulfonamide unit, whereas in the case of PUBO, a good hydrogen-bonding donor, the ESIPT process is inhibited either by the fluoride-induced deprotonation of the urea unit or by the formation of a strong CH3COO--urea intermolecular hydrogen bond complex, and these two types of inhibition mechanisms consequently result in different ratiometric responses. But other anions with less hydrogen-bonding acceptor abilities cannot inhibit the ESIPT, Interestingly, the different inhibition abilities of F-, CH 3COO-, and H2PO4- produce different spectral behaviors in PUBO, so this new sensor successfully distinguishes the subtle difference in these three anionic substrates of similar basicity and surface charge density.
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U2 - 10.1021/jo061634c
DO - 10.1021/jo061634c
M3 - Article
C2 - 17194082
AN - SCOPUS:33846100702
SN - 0022-3263
VL - 72
SP - 62
EP - 70
JO - Journal of Organic Chemistry
JF - Journal of Organic Chemistry
IS - 1
ER -