Reversible Addition of Alkynes to Gallium Complex of Chelating Diamide Ligand

Different alkynes add reversibly to the gallium complex of the dpp-Bian dianion. The reactions proceed with addition of the alkynes the Ga-N-C fragment resulting in carbon-carbon and carbon-gallium bonds. In the case of 3 and 4 a full elimination of the alkyne takes place at T < 100 degrees C, whereas with adducts 5 and 6 it occurs at heating to ca. 200 degrees C.