Syntheses and Structures of Water-Soluble Model Complexes Related to the Active Site of Molybdenum and Tungsten-Dependent Oxidoreductases

Abstract

Among the many structural model complexes for the molybdenum and tungsten dependent oxidoreductases, none are specifically highlighted as being water stable and water soluble, and only very few may have such potential. Herein, complex salts with potassium cations and bisdithiolene oxido molybdate or tungstate anions are described, which were designed to be water-tolerant and soluble in purely aqueous medium. Four different routes to water-soluble complexes of the type K2[MOx(dt)2] (M = Mo, W; dt = ene-1,2-dithiolate, x = 1, 2) are presented, the applicability of which depends on the varied, distinct ligand precursors. The crystal structures of the salts are examined in detail, with particular attention to cation–anion interactions, alongside an analysis of the corresponding infrared spectra to support structural interpretations and interaction characteristics.