Reactions of Sodium Hydrogentelluride with α-Azido Ketones and α-Azido Bromides

When treated with sodium hydrogentelluride in ethanol at room temperature, α-azido ketones are easily converted to pyrazines via the self-condensation of initially formed α-amino ketones followed by aerobic oxidation during work-up. On a similar treatment, activated α-azido bromide such as 1,2-diphenyl-1-azido-2-bromoethane suffers E2-type β-elimination to give the corresponding olefin as the sole product, while ordinary α-azido bromides afford complicated mixtures containing amino and olefinic compounds among other products.