title: Computational Design of Iron Diphosphine Complexes with Pendant Amines for Hydrogenation of CO2 to Methanol: A Mimic of [NiFe] Hydrogenase.
abstract: Inspired by the active-site structure of the [NiFe] hydrogenase, we have computationally designed the iron complex [P(tBu) 2 N(tBu) 2 )Fe(CN)2 CO] by using an experimentally ready-made diphosphine ligand with pendant amines for the hydrogenation of CO2 to methanol. Density functional theory calculations indicate that the rate-determining step in the whole catalytic reaction is the direct hydride transfer from the Fe center to the carbon atom in the formic acid with a total free energy barrier of 28.4 kcal mol(-1) in aqueous solution. Such a barrier indicates that the designed iron complex is a promising low-cost catalyst for the formation of methanol from CO2 and H2 under mild conditions. The key role of the diphosphine ligand with pendent amine groups in the reaction is the assistance of the cleavage of H2 by forming a Fe-H(δ-) ⋅⋅⋅H(δ+) -N dihydrogen bond in a fashion of frustrated Lewis pairs.
authors.affiliation: Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P.R. China.|University of Chinese Academy of Sciences, Beijing, 100049, P.R. China.
authors.forename: Xiangyang
authors.initials: X
authors.lastname: Chen
authors.affiliation: Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P.R. China.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Jing
authors.affiliation: Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P.R. China. xyang@iccas.ac.cn.
authors.forename: Xinzheng
authors.initials: X
authors.lastname: Yang
mesh_terms: D000588:Amines / Q000737:chemistry*; D002245:Carbon Dioxide / Q000737:chemistry*; D002384:Catalysis; D020134:Catalytic Domain; D056831:Coordination Complexes / Q000737:chemistry*; D005561:Formates / Q000737:chemistry; D006859:Hydrogen / Q000737:chemistry; D006864:Hydrogenase / Q000737:chemistry / Q000378:metabolism; D006865:Hydrogenation; D007501:Iron / Q000737:chemistry*; D000432:Methanol / Q000737:chemistry*; D008968:Molecular Conformation; D010720:Phosphines / Q000737:chemistry; D013816:Thermodynamics
chemical_list: D000588:Amines; D056831:Coordination Complexes; D005561:Formates; D010720:Phosphines; C030544:formic acid; D002245:Carbon Dioxide; D006859:Hydrogen; D007501:Iron; C043296:nickel-iron hydrogenase; D006864:Hydrogenase; C044646:phosphine; D000432:Methanol
keywords: carbon dioxide; density functional calculations; hydrogenases; hydrogenation; methanol