918545-09-2Relevant academic research and scientific papers
Thioether sulfur oxygenation from O2 or H2O 2 reactivity of copper complexes with tridentate N2S thioether ligands
Lee, Yunho,Lee, Dong-Heon,Narducci Sarjeant, Amy A.,Zakharov, Lev N.,Rheingold, Arnold L.,Karlin, Kenneth D.
, p. 10098 - 10107 (2006)
To model thioether-copper coordination chemistry including oxidative reactivity, such as occurs in the copper monooxygenases peptidylglycine α-hydroxylating monooxygenase (PHM) and dopamine β-hydroxylase (DβH), we have synthesized new tridentate N2S ligands L SEP and LSBz [LSEP = methyl(2- phenethylsulfanylpropyl)(2-pyridin-2-ylethyl)amine; LSBz = (2-benzylsulfanylpropyl)methyl(2-pyridin-2-ylethyl)amine)]. Both copper(I) and copper(II) complexes have been prepared, and their respective O2 and H2O2 chemistry has been studied. Under mild conditions, oxygenation of [(LSEP)CuI]+ (1a) and [(L SBz)CuI]+ (2a) leads to ligand sulfoxidation, thus exhibiting copper monooxygenase activity. A copper(II) complex of this sulfoxide ligand product, [(LSOEP)CuII(CH 3OH)(OClO3)2], has been structurally characterized, demonstrating Cu-OsulfoXide ligation. The X-ray structure of [(LSEP)CuII(H2O)(OClO 3)]+ (1b) and its solution UV-visible spectral properties [S-CuII LMCT band at 365 nm (MeCN solvent); ε = 4205 M -1 cm-1] indicate the thioether sulfur atom is bound to the cupric ion in both the solid (CuII-S distance: 2.31 A) and solution states. Reaction of 1b with H2O2 leads to sulfonation via the sulfoxide; excess hydrogen peroxide gives mostly sulfone product. These results may provide some insight into recent reports concerning protein methionine oxidation, showing the potential importance of copper-mediated oxidation processes in certain biological settings.
