title: Syntheses, spectroscopies and structures of molybdenum(VI) complexes with homocitrate.
abstract: Initial investigations into the possible role of homocitric acid in iron molybdenum cofactor (FeMo-co) of nitrogenase lead us to isolate and characterize two tetrameric molybdate(VI) species. The complexes K2(NH4)2[(MoO2)4O3(R,S-Hhomocit)2].6H2O (1) and K5[(MoO2)4O3(R,S-Hhomocit)2]Cl.5H2O (2) (homocitric acid = H4homocit, C7H10O7) are prepared from the reactions of acyclic homocitric acid and molybdates, which represent the first synthetic structural examples of molybdenum homocitrate complexes. The homocitrate ligand trapped by tetranuclear molybdate coordinates to the molybdenum(VI) atom through alpha-alkoxy and alpha-, beta-carboxy groups. The physical properties, structural parameters, and their possible biological relevances are discussed.
authors.affiliation: Department of Chemistry, College of Chemistry and Chemical Engineering and State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen 361005, China. zhzhou@xmu.edu.cn
authors.forename: Zhao-Hui
authors.initials: ZH
authors.lastname: Zhou
authors.forename: Shu-Ya
authors.initials: SY
authors.lastname: Hou
authors.forename: Ze-Xing
authors.initials: ZX
authors.lastname: Cao
authors.forename: Khi-Rui
authors.initials: KR
authors.lastname: Tsai
authors.forename: Yuan L
authors.initials: YL
authors.lastname: Chow
mesh_terms: D018360:Crystallography, X-Ray; D009682:Magnetic Resonance Spectroscopy; D008982:Molybdenum / Q000737:chemistry*; D008983:Molybdoferredoxin / Q000737:chemistry; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D014233:Tricarboxylic Acids / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: D008983:Molybdoferredoxin; D009942:Organometallic Compounds; D014233:Tricarboxylic Acids; C044659:molybdate; C028143:homocitric acid; D008982:Molybdenum