Synthesis and Study of 2-(2-Thienyl)benzazole Type Fluorophores

Abstract

Reaction of 2-(mercaptomethyl)benzazoles 2a–c or isothiouronium salt 4 with acetyleneketone 5 or β-halogeno-α,β-unsaturated aldehyde 7 gives highly fluorescent heterocycles 6a–c or 8a–d. The fluorescence properties of these compounds and their aromatised derivatives 9a,b were investigated.

Keywords:

• Benzazoles
• Vilsmeyer-Hack reaction
• Fluorescent dye
• Fiesselmann reaction

Acknowledgment

This work was supported by grant from Hungarian National Research Foundations (OTKA T34307 and M 028226). The authors thank to Prof. Neil V. Blough (Univeristy of Maryland, College Park, USA) for the possibility and helpful discussions in fluorescence measurements and M. Szabó for mass spectral measurements (ICN, Hungary). One of authors (T. K.) thanks for Eötvös fellowship for Hungarian Ministry of Education.