Isolation and Crystal Structure of the Proposed Low-Valent Active Species in the H2 Activation Catalytic Cycle

We provide confirmation of our proposed design principles for a H2 activation catalytic cycle by constructing a new catalyst. We have been able to obtain a crystal structure to confirm our proposition that a reduced, dinuclear species stores electrons from hydrogen molecules in a metal–metal bond. A two‐electron‐reduced dinuclear IrII–IrII complex was synthesized by the reaction of a mononuclear IrIII aqua complex by extraction of electrons from H2 in water under ambient conditions.