Reduction of Cp*2Mo2O5 dimer by thioglycolic acid in an aqueous medium: Synthesis and structure of [{Cp*Mo(µ-SCH2COO)}2(µ-S)]

In this study ?high oxidation state organometallic chemistry? in aquoeus medium, the oxidation- +reactions of the salt [Cp*M(CO)3] Na (M= Mo, W) with H2O2 in acidic and basic conditions (NaOH,NaOCl, HNO3) have been examined and the structures of products have been investigated byspectroscopy methods (1H NMR, IR).The compound Cp*2M2O5 (M= Mo, W) couldn?t be obtained purely in high yield instead dimerof [Cp*M(CO)3]2 (M= Mo, W) have been obtained as the main product.As a result of the reduction of Cp*2Mo2O5 with thyoglikolic acid (HSCH2COOH) in MeOH-H2Omedium and existence of CF3COOH, [Cp*Mo(µ-SCH2COO)]2(µ-S)] have been examined. During thisreaction, the thioglikolic asid acts as a natural reducing agent of Mo (VI) into Mo (IV), as a ligand, andas a substrate for C-S bond reduction. The structures of products have been investigated by1spectroscopy methods (Mass, H NMR, EPR) and single crystal X-Ray difractometry. The structure ofthe compound have been reported as containing two four-legged piano stools that share three legs.The Mo-Mo distance of 2.792(7) Å indicates metal-metal bonding, in agreement with thecompound diamagnetism.The struct of the product of the reaction of Cp*2Mo2O5 with thyoglikolic acid (HSCH2COOH) inMeOH-H2O medium and existence of CH3COOH couldn?t be identified.The reduction reaction of Cp*2Mo2O5 with 2-metil-2-propantiyol ((CH3)3CSH) in MeOH-H2Omedium and existence of CF3COOH have been obtained and after examining the 1H NMR results oftthe product it?s reported that it can be the complex Cp*Mo(O)2(S Bu).Key Words: Carboxilato ligands, C-S Bond Activation, Hydroxo Ligands, Metal-Metal Bonds,Molybdenum, Oxo Ligands, Aqueous Organometallic Chemistry, Tungsten