title: Synthesis, optical properties and explosive sensing performances of a series of novel π-conjugated aromatic end-capped oligothiophenes.
abstract: Four novel terthiophene (3T) derivatives, have been synthesized by employing Grignard coupling reaction via end-capping of naphthyl (NA) or pyrenyl (Py) unit to the one or two ends of 3T. It has been shown that both increasing electron donating strength and extending conjugation are effective approaches to improve the photochemical stability of the oligothiophene. Fluorescence studies demonstrated that the emission of the 3T derivatives is sensitive to the presence of some important nitro-containing explosives in their ethanol solution, in particular, 2,4,6-trinitrophenol (PA) and 3,5-dinitro-2,6-bispicrylamino pyridine (PYX). As an example, the detection limits of 4 to PA and PYX were determined to be 6.21 × 10(-7)mol/L and 8.95 × 10(-7)mol/L, respectively. Based on the discovery, a colorimetric detection method has been developed. The sensitive and selective response of the modified 3T to the explosives have been tentatively attributed to the adsorptive affinity of the compounds to the explosives, and to the higher probability of the electron transfer from the electron-rich 3T derivatives to the electron-poor nitro-containing explosives. No doubt, present study broadens the family of fluorophores which may be employed for the development of fluorescent sensors.
authors.affiliation: Key Laboratory of Applied Surface and Colloid Chemistry of Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an 710062, PR China.
authors.forename: Taihong
authors.initials: T
authors.lastname: Liu
authors.forename: Keru
authors.initials: K
authors.lastname: Zhao
authors.forename: Ke
authors.initials: K
authors.lastname: Liu
authors.forename: Liping
authors.initials: L
authors.lastname: Ding
authors.forename: Shiwei
authors.initials: S
authors.lastname: Yin
authors.forename: Yu
authors.initials: Y
authors.lastname: Fang
mesh_terms: D000431:Ethanol; D053834:Explosive Agents / Q000032:analysis*; D005453:Fluorescence; D009574:Nitro Compounds / Q000032:analysis*; D013876:Thiophenes / Q000737:chemistry*
chemical_list: D053834:Explosive Agents; D009574:Nitro Compounds; D013876:Thiophenes; C019101:alpha-terthienyl; D000431:Ethanol