Synthesis and characterization of a pyrene-based Schiff base and its oligomer: Investigation of fluorescent Cr3+ probe

In this study, a unique Schiff base (SP) was synthesized from 1-aminopyrine (1-AP) and salicylaldehyde (SA) compounds. The obtained oligomer of this Schiff base was carried out by the oxidative polymerization method. The structural characterizations of 2-((pyren-1-yl-imino)methyl)phenol (SP) and oligo-2-((pyren-1-yl-imino)methyl)phenol (OSP) by FT-IR, H-1 NMR and C-13 NMR measurements, electrochemical properties by cyclic voltammetry (CV); optical properties by UV/Vis studies and photoluminescence (PL) spectrophotometry; thermal stability were performed by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The molecular weight of the obtained oligomer was determined using gel permeation chromatography (GPC). Accordingly, Mn and Mw values of OSP were found to be 2800 and 3150 Da, respectively. The imine bond provided the structures with high thermal stability, and the maximum mass loss temperatures (T-max) of SP and OSP were found to be 350(0) and 343 degrees C, respectively. PL study showed that SP could be used as a Cr3+ sensor among a series of metals. The results revealed that the limit of detection (LOD) value of SP was 1.03 x 10(-)(9) M and was not affected by other ions in the environment.

Automated summary

In this study, a unique Schiff base and its oligomer were synthesized and characterized. The Schiff base showed high thermal stability and exhibited potential as a Cr3+ sensor. The results provide valuable insights into the structural, electrochemical, optical, and thermal properties of the synthesized compounds.