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N-H Bond Formation at a Diiron Bridging Nitride.

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 ?-amide product. The structurally analogous ?-silyl- and ?-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 NH₃ in high yield through a reaction that engages the redox-activity of the ligand during PCET.

SUBMITTER: Zhang S

PROVIDER: S-EPMC7680347 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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N-H Bond Formation at a Diiron Bridging Nitride.

Zhang Shaoguang S Cui Peng P Liu Tianchang T Wang Qiuran Q Longo Thomas J TJ Thierer Laura M LM Manor Brian C BC Gau Michael R MR Carroll Patrick J PJ Papaefthymiou Georgia C GC Tomson Neil C NC

Angewandte Chemie (International ed. in English) 20200609 35

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-boryl ...[more]

PMID: 32441448

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