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Updated: Dec 30, 2025
Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
Conformational Restrictions in meso-(2-Thiazolyl)-BODIPYs: Large Stokes Shift and pH-Dependent Optical Properties
Kalluvettukuzhy K Neena1, Pakkirisamy Thilagar1
1Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, 560012, India.
Abstract:
The design, synthesis, and characterization of a series of thiazole-appended boron-dipyrromethene (BODIPY) derivatives 1-4 is reported. The fluorescence emission colors of 1-4 were fine-tuned by modulating the dihedral angle between BODIPY and thiazole by judiciously varying the number of methyl substituents on both the BODIPY and thiazole moieties. Compounds 1 and 2 with fewer methyl substituents on the BODIPY core showed a large Stokes shift (≈110 nm) relative to derivatives 3 and 4 with more methyl substituents. In addition, the optical properties of 1 and 2 are sensitive to the pH of the medium. The experimentally observed results were corroborated with theoretical calculations.
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