N(2) activation on a molybdenum–titanium–sulfur cluster

The FeMo-cofactor of nitrogenase, a metal–sulfur cluster that contains eight transition metals, promotes the conversion of dinitrogen into ammonia when stored in the protein. Although various metal–sulfur clusters have been synthesized over the past decades, their use in the activation of N(2) has remained challenging, and even the FeMo-cofactor extracted from nitrogenase is not able to reduce N(2). Herein, we report the activation of N(2) by a metal–sulfur cluster that contains molybdenum and titanium. An N(2) moiety bridging two [Mo(3)S(4)Ti] cubes is converted into NH(3) and N(2)H(4) upon treatment with Brønsted acids in the presence of a reducing agent.