N−H Bond Formation at a Diiron Bridging Nitride
Shaoguang Zhang, Peng Cui, Tianchang Liu, Qiuran Wang, Thomas J. Longo, Laura M. Thierer, Brian C. Manor, Michael R. Gau, Patrick J. Carroll, Georgia C. Papaefthymiou, Neil C. Tomson
Abstract
Abstract Despite their connection to ammonia synthesis, little is known about the ability of iron‐bound, bridging nitrides to form N−H bonds. Herein we report a linear diiron bridging nitride complex supported by a redox‐active macrocycle. The unique ability of the ligand scaffold to adapt to the geometric preference of the bridging species was found to facilitate the formation of N−H bonds via proton‐coupled electron transfer to generate a μ ‐amide product. The structurally analogous μ ‐silyl‐ and μ ‐borylamide complexes were shown to form from the net insertion of the nitride into the E−H bonds (E=B, Si). Protonation of the parent bridging amide produced ammonia in high yield, and treatment of the nitride with PhSH was found to liberate NH 3 in high yield through a reaction that engages the redox‐activity of the ligand during PCET.