Synthesis of Unsymmetrical Aza-Ullazines by Intramolecular Alkynyl-Carbonyl Metathesis.

A variety of aza-ullazines were synthesized in one step from readily accessible 3,5-dialkynyl-4-pyrrolopyridine via acylation followed by intramolecular alkynyl carbonyl metathesis. The reaction conditions were optimized, and the preparative scope was studied. The optoelectronic properties of selected aza-ullazines were studied by UV/vis and fluorescence spectroscopy.