Dinitrogen Cleavage by a Heterometallic Cluster Featuring Multiple Uranium-Rhodium Bonds

摘要

Reduction of dinitrogen (N_2) is a major challenge for chemists. Cooperation of multiple metal centers to break the strong N_2 triple bond has been identified as a crucial step in both the industrial and the natural ammonia syntheses. However, reports of the cleavage of N_2 by a multimetallic uranium complex remain extremely rare, although uranium species were used as catalyst in the early Harber-Bosch process. Here we report the cleavage of N_2 to two nitrides by a multimetallic uranium-rhodium cluster at ambient temperature and pressure. The nitride product further reacts with acid to give substantial yields of ammonium. The presence of uranium-rhodium bond in this multimetallic cluster was revealed by X-ray crystallographic and computational studies. This study demonstrates that the multimetallic clusters containing uranium and transition metals are promising materials for N_2 fixation and reduction.