Resumen de Ammonia activation at a metal
Although ammonia (NH3) is made on a vast scale for use in fertilizers, its use as a chemical feedstock or as an energy carrier is much more limited. Many reactions that occur easily with its substitution products (amines) are sluggish for NH3, in part because of the difficulty of activating the N-H bond. For fuel cells, NH3 is attractive because it does not generate greenhouse gases, as do methanol and methane (1), and is more easily stored than hydrogen (H2). Amine-containing organic molecules are used in pharmaceutical and materials applications, and accessing these structures directly from ammonia could limit the generation of by-products during their synthesis (2). Bringing NH3 up to speed for these applications will require both the development of catalysts that can activate the strong N–H bond of ammonia and a fundamental understanding of the N–H bond cleavage step. On page 730 of this issue, Bezdek et al. (3) report a molybdenum complex capable of weakening the N–H bond of NH3 and releasing a H atom to generate H2 under mild conditions.
