Solvatochromic Fluorescent 2‑Substituted 3‑Ethynyl Quinoxalines: Four-Component Synthesis, Photophysical Properties, and Electronic Structure

2-Substituted
3-ethynylquinoxalines can be rapidly synthesized
in generally excellent yields by a consecutive four-component synthesis
starting from electron-rich π-nucleophiles, oxalyl chloride,
terminal alkynes, and 1,2-diaminoarenes. The title compounds are highly
fluorescent with a pronounced emission solvatochromism. The photophysical
properties and electronic structure were additionally corroborated
by computations on the DFT level of theory.