Synthesis and Hydrolysis of Thiol Derivatives of Molybdocene Dichloride Incorporating Electron-Withdrawing Substituents

Hydrolysis studies of derivatives of molybdocene dichloride in which the two chloride ligands were
replaced by 3,5-bis(trifluoromethyl)thiophenol, 3,5-bis(trifluoromethyl)benzyl thiol, and 2,2,2-trifluoroethane thiol ligands confirmed that the electron-withdrawing groups affect the lability of the Mo−S
bonds and promote slow generation of the putative biologically active species “Cp2Mo2+”; the
trifluoroethane thiol derivative underwent 50% hydrolysis in 14 h in 10% D2O/DMSO-d6. The structure
of molybdocene bis(S-3,5-bis(trifluoromethyl)benzyl thiol) was confirmed by X-ray crystal structure
analysis.