title: Systematic investigation of relationship between strength of NH···S hydrogen bond and reactivity of molybdoenzyme models.
abstract: A series of monooxomolybdenum(IV) and dioxomolybdenum(VI) complexes containing two intramolecular NH···S hydrogen bonds were synthesized and characterized by (1)H NMR, UV-visible, IR, and Raman spectroscopies, and electrochemical measurements. Elimination of the steric effects enabled the accurate and quantitative evaluation of NH···S hydrogen bonds. Strong correlations among the strength of the hydrogen bond, the strength of the Mo(VI)═O bond, and the redox potential were clearly shown. The hydrogen bonds stabilize the intermediate in the reaction between the monooxomolybdenum(IV) and Me(3)NO, resulting in acceleration of the reaction or retardation of trans-cis rearrangement. The proposed intermediate and the reaction mechanism, discussed on the basis of theoretical calculations, provided a unified explanation of the reaction.
authors.affiliation: Department of Macromolecular Science, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan. tokamura@chem.sci.osaka-u.ac.jp
authors.forename: Taka-aki
authors.initials: TA
authors.lastname: Okamura
authors.forename: Yasuhito
authors.initials: Y
authors.lastname: Ushijima
authors.forename: Yui
authors.initials: Y
authors.lastname: Omi
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Onitsuka
mesh_terms: D006860:Hydrogen Bonding; D008024:Ligands; D008958:Models, Molecular; D008982:Molybdenum / Q000737:chemistry*; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D011789:Quantum Theory; D013237:Stereoisomerism
chemical_list: D008024:Ligands; D009942:Organometallic Compounds; D008982:Molybdenum