Free-radical azidation with γ-15N-labeled phenylsulfonyl azide

The gamma-nitrogen of phenylsulfonyl azide can be readily labeled with N-15 by treating benzenesulfonyl hydrazide with (NaNO2)-N-15. The resulting gamma-N-15-labeled sulfonyl azide reacts with carbon-centered free radicals to produce alkyl azides exclusively containing a C-N-15 bond. This chemistry provides valuable insight into the free-radical azidation mechanism as well as providing a mild method for the production of N-15-amines.