Synthesis and Spectral Properties of 1,2-Bispyrazyl Ethylene

[摘要] A new compound, 1,2-bispyrazyl ethylene,is synthesized starting from pyrazine carboxylic acid and methyl pyrazine. The compound is characterized utilizing UV-VIS, IR, NMR and mass spectra along with elemental analysis. Spectroscopic properties are studied from UV-VIS and fluorescence spectra. From unusual salt effects on fluorescence spectra, it is believed that (n,¥ð*)1 state has about the same energy as (¥ð,¥ð*)1 state. The compound fluoresces from (¥ð,¥ð*)1 state with the quantum yield of 0.025 at 77¡£K compared to near unity for stilbene at the same temperature indicating the efficient intersystem crossing to triplet state, because of strong (n,¥ð*) and (¥ð,¥ð*) mixing in the lowest excited state.

[学科分类] 化学（综合）