title: N-N bond cleavage of hydrazines with a multiproton-responsive pincer-type iron complex.
abstract: N-N bond cleavage of hydrazines on transition metals is of considerable importance in understanding the mechanism of biological nitrogen fixation under ambient conditions. We found that a metal-ligand-bifunctional complex of iron with a pincer-type ligand bearing two proton-responsive pyrazole arms catalyzes the disproportionation of hydrazine into ammonia and dinitrogen. The NH groups in the pyrazole ligands and hydrazines are crucial for the reaction, which most likely occurs through multiple and bidirectional proton-coupled electron transfer between the iron complex and hydrazine. The multiproton-responsive pincer-type ligand also stabilizes the intermediate diazene complex through a hydrogen-bonding network, as revealed by structural characterization of a κ(1)N-phenylhydrazine complex.
authors.affiliation: Department of Applied Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, Meguro-ku, Tokyo, Japan.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Umehara
authors.forename: Shigeki
authors.initials: S
authors.lastname: Kuwata
authors.forename: Takao
authors.initials: T
authors.lastname: Ikariya
mesh_terms: D005296:Ferrous Compounds / Q000737:chemistry*; D006834:Hydrazines / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D011522:Protons
chemical_list: D005296:Ferrous Compounds; D006834:Hydrazines; D011522:Protons