New pyrazole−porphyrin conjugates were successfully prepared froma reaction of β-porphyrin−chalcone derivatives with phenylhydrazine in acetic acidfollowed by an oxidative step. This fast and efficient synthetic approach provided theexpected compounds in yields up to 82%. The sensing ability of the new porphyrin−pyrazole derivatives to detect the metal ions Ag+, Na+, K+, Mg2+, Ca2+, Ni2+, Cu2+,Zn2+, Cd2+, Hg2+, Pb2+, and Cr3+ was studied by spectrophotometric and spectrofluorimetric titrations. In the presence of Zn2+,the conjugates exhibit changes in the emission spectra that are desired for a ratiometric-type fluoroionophoric detection probe.The studies were extended to gas phase, where the pyrazole−porphyrin conjugates show ability to sense metal ions with highselectivity toward Cu2+ and Ag+, and in poly(methyl methacrylate) doped films with promising results for Zn2+ detection.
Moura, N. M. M., Nunez, C., Santos, S. M., Faustino, M. A. F., Cavaleiro, J. A. S., Neves, M. G. P. M. S., Capelo, J. L., & Lodeiro, C. (2014). Synthesis, Spectroscopy Studies, and Theoretical Calculations of New Fluorescent Probes Based on Pyrazole Containing Porphyrins forZn(II), Cd(II), and Hg(II) Optical Detection. Inorganic Chemistry, 53(12), 6149-6158. https://doi.org/10.1021/ic500634y