Abstract:

3-Phenyl-pyrrolo[2,1,5-cd]indolizine-1-carboxylic acid(2-hydroxy-benzylidene)-hydrazide(6) was synthesized and used as fluorescent sensors for Cu²⁺ ion. The structure of the compound 6 was determined by IR, ¹H NMR, MS and elemental analysis and their UV and fluorescence spectra were measured. The influences of ten metal ions such as Cu²⁺, Zn²⁺, Ni²⁺, Co²⁺, Al³⁺, Cr³⁺, Mn²⁺, Na⁺, Sn²⁺ and Ca²⁺ on their fluorescence properties were studied. Spectroscopic studies revealed that the compound 6 had rather strong affinity toward Cu²⁺. The specificity of the probe 6 toward Cu²⁺ was determined. Nearly no fluorescence intensity changes were observed in emission spectra with Zn²⁺, Ca²⁺, Na⁺, K⁺, Cr³⁺, Sn²⁺, Al³⁺ but Ni²⁺ and Co²⁺. However, under identical conditions, the results showed fluorescence quenching with Cu²⁺. So we have developed a new fluorescent sensor 6. It shows high sensitivity and selectivity toward Cu²⁺ in DMSO.

Key words: 3-Phenyl-pyrrolo[2,1,5-cd]indolizine-1-carboxylic acid(2-hydroxy-benzylidene)-hydrazide, Cu²⁺, Fluorescence probe