Synthesis and properties of benzothiadiazole-pyridine system: The modulation of optical feature

Bipyridine-substituted compound 1 was successfully synthesized via the modified Buchwald-Hartwig amination route with relatively high yield in relatively short reaction time. The relatively rigid derivative 2 was subsequently prepared by the simple dehydrogenation. Herein, two new BTD-pyridine compounds 1 and 2 show the attracting modulation of optical capability by the change of molecular polarity feature. In comparison with 1, polarized nature was declined in dehydrogenated 2, indicating the blue-shifted absorption and emission as well as weakened negative cubic nonlinear refraction.216