title: Synthesis, structures and electrochemical properties of nitro- and amino-functionalized diiron azadithiolates as active site models of Fe-only hydrogenases.
abstract: Complex [[(mu-SCH2)2N(4-NO2C6H4)]Fe2(CO)6] (4) was prepared by the reaction of the dianionic intermediate [(mu-S)2Fe2(CO)6](2-) and N,N-bis(chloromethyl)-4-nitroaniline as a biomimetic model of the active site of Fe-only hydrogenase. The reduction of 4 by Pd-C/H2 under a neutral condition afforded complex [[(mu-SCH2)2N(4-NH2C6H4)]Fe2(CO)6] (5) in 67 % yield. Both complexes were characterized by IR, 1H and 13C NMR spectroscopy and MS spectrometry. The molecular structure of 4, as determined by X-ray analysis, has a butterfly 2Fe2S core and the aryl group on the bridged-N atom slants to the Fe(2) site. Cyclic voltammograms of 4 and 5 were studied to evaluate their redox properties. It was found that complex 4 catalyzed electrochemical proton reduction in the presence of acetic acid. A plausible mechanism of the electrocatalytic proton reduction is discussed.
authors.affiliation: State Key Laboratory of Fine Chemicals, Dalian University of Technology, Zhongshan Road 158-46, Dalian 116012, China.
authors.forename: Tianbiao
authors.initials: T
authors.lastname: Liu
authors.forename: Mei
authors.initials: M
authors.lastname: Wang
authors.forename: Zhan
authors.initials: Z
authors.lastname: Shi
authors.forename: Hongguang
authors.initials: H
authors.lastname: Cui
authors.forename: Weibing
authors.initials: W
authors.lastname: Dong
authors.forename: Jiesheng
authors.initials: J
authors.lastname: Chen
authors.forename: Björn
authors.initials: B
authors.lastname: Akermark
authors.forename: Licheng
authors.initials: L
authors.lastname: Sun
mesh_terms: D001372:Aza Compounds / Q000737:chemistry*; D018360:Crystallography, X-Ray; D004563:Electrochemistry; D006864:Hydrogenase / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D007506:Iron-Sulfur Proteins / Q000737:chemistry*; D008958:Models, Molecular; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry; D013438:Sulfhydryl Compounds / Q000737:chemistry*
chemical_list: D001372:Aza Compounds; D007506:Iron-Sulfur Proteins; D009942:Organometallic Compounds; D013438:Sulfhydryl Compounds; D007501:Iron; C118830:iron hydrogenase; D006864:Hydrogenase