On the option of generating novel type surfaces with multiphilic ligands within the cavity of a giant metal-oxide based wheel type cluster: Chemical reactions with well-defined nanoobjects

Abstract

The reaction of an aqueous solution of sodium molybdate with cysteine hydrochloride acting as educt and reducing agent at rather low pH values (≈1.5) results in the formation of Na3[MO154O462H14(H2O) 48(HO2C-(NH3+)HC-CH2 -S-S-CH2-CH(NH3+)- COO-)11]·x H2O 1 (x ≈ 250) containing nanosized ring-shaped clusters which capture the oxidation product of cysteine, i.e. the diprotonated cystine ligands (H2cystine+) at the inner wall of their cavities; interestingly, the multiphilic ligands containing different types of functional groups (two -NH3+, one -CO2-, one -CO2H and one -S-S-) attach to the inner wall of the cluster through one of the two carboxylate groups thereby demonstrating the possibility to generate novel type surfaces within the cavity of a nanostructured ring-shaped cluster.