Molybdenum complexes with O,N,S donor ligands as models for active sites in oxotransferases and hydroxylases

A series of homologous mononuclear dioxomolybdenum complexes were prepared and fully characterized with structurally related thiosemicarbazone ligands supplying a tridentate O,N,S donor set to the central metal atom. The ligands are derived from the prototype 2-hydroxybenzaldehyde-4-triphenylmethylthiosemicarbazone (H2L). Within this series the crystal structures of 11 complex compounds [MoO2(LRn)(dmf)] and [MoO2(LRn)(MeOH)] were determined showing characteristic differences in the gross structural properties of the central metal core. From the variation of substituents in this ligand library the influences of electronic ligand effects on the spectroscopic, electrochemical, and functional properties of these biomimetic model complexes for molybdenum-containing oxotransferases are reported.

Graphical abstractA library of functionalized derivatives of the tridentate O, N, S donor ligand 2-hydroxobenzaldehyde-4-triphenylmethylthiosemicarbazone was employed to synthesize a series of mononuclear dioxomolybdenum complexes. Their properties as possible biomimetic models for molybdenum-containing oxotransferases and hydroxylases are studied.Figure optionsDownload full-size imageDownload as PowerPoint slide