Benzylidenecyclohexanone-triazole-based conjugated polymer: Click synthesis, Staudinger end-capping and application as optical probe scaffold

A type of benzylidenecyclohexanone-triazole based conjugated polymer (P5) was successfully synthesized by Cu+-catalyzed Click reaction. The THE solution of P5 exhibited specific optical response (increase in absorption and decrease in fluorescence) toward I. With the further addition of Hg2+ into the assembly of P5-I-, distinctive recovery of optical properties was detected, suggests that P5-I- adduct can act as fluorescence turn-on probing platform for Hg2+. Post-polymerization of P5 was implemented by catalyst-free Staudinger reaction between P5 and triphenylphosphine to afford phosphinimine-endcapped polymer (P5-TPP). Different from the blue-greenish emission (similar to 490 nm) of P5, P5-TPP emitted yellow light (similar to 550 nm) in THE water mixture (V-THF/V-water = 2/8). P5-TPP displayed specific fluorescence ratiometric alteration toward hypochlorite ion in THE water mixture (V-THF/V-water = 2/8, pH = 7.4), which might be due to the hypochlorite-induced hydrolysis of phosphinimine energy-transfer acceptors in P5-TPP. The results suggest that P5 can act as structure scaffold for the construction of optical probe for triple analytes (I-, Hg2+ and ClO-). (C) 2016 Elsevier Ltd. All rights reserved.