Sulfurization And Structural Characterization Of Tungsten/Molybdenum Oxygen(Carbonyl) Complexes Stabilized By Me₃tacn Ligand

Transition metal sulfide(TMS) system plays an extremely important role in the development of biological enzymes and industry and have been widely applied in the fields of bionic chemistry,electro-and photo-catalysis,corrosion,lubrication,metal oxide semiconductor,oxidation resistance and battery technology.Zero-valent tungsten/molybdenum compounds[(Me₃tacn)M(CO)₃](M=W 1a,Mo 1b)were readily prepared,and then penta-valent tungsten/molybdenum compounds[(Me₃tacn)Mo Cl₂]PF₆(M=W 2a,Mo 2b)were synthesized by using of1a and 1b as starting materials in this thesis.Hexa-valent tungsten/molybdenum compounds[(Me₃tacn)MO₃](M=W 3a,Mo 3b)were prepared by directly reflux reaction of Me₃tacn with[MO₃](M=W,Mo)in distilled water.The zero-,penta-,and hexa-valent tungsten/molybdenum compounds containing Me₃tacn ligands were used as starting materials to react with a series of sulfur reagents,such as sulfur powder,alkyldithiocarbamate and Na₂S,etc.The compound[(Me₃tacn)WO₂S](4a)containing a single terminal W=S bond and the oxotetrasulfido compound[(Me₃tacn)Mo O(S₄)](5)were obtained by refluxation of compounds 1a and 1b with excess sulfur powder in acetonitrile,respectively.Treatment of compound 2a with sodium diisopropyl dithiocarbamate in acetonitrile in the presence of silver nitrate afforded the silver thiolate cluster[Ag₆(S₂CNⁿPr₂)₆](9)as a by-product.The hydrolysate[{(Me₃tacn)Mo O(OH)}₂(?-O)](PF₆)₂(7)was afforded by the hydrolysis reaction of penta-valent molybdenum compound 2b with sodium diisopropyl dithiocarbamate in acetonitrile.After protonation of compound 3b with an equal of hexafluorophosphoric acid followed by sulfurization by diisopropyl dithiocarbamate,compound 4b with a single terminal Mo=S bond was obtained.The similar reaction using 3b,2 equiv.hexafluorophosphoric acid and diisopropyl dithiocarbamate at reflux in acetonitrile resulted in isolation of the oxotetrasulfido compound[(Me₃tacn)Mo O(S₄)](5).Similarly,when 3 eqiv.hexafluorophosphoric acid was used in the protonation reaction,compounds[(Me₃tacn)Mo O(S₄)](5),[(Me₃tacn)Mo O(OH)₂](PF₆)₂(6)and[(Me₃tacn)Mo O₂S](ⁱPR₂NH₂)(PF₆)·CH₂Cl₂(8)were obtained as well as the by-product[Mo(S₂CNⁱPr₂)₄]PF₆(10).The molecular structures of compounds 4a,4b and 5-10 have been unambiguously established by single-crystal X-ray crystallography,and the products containing Me₃tacn groups were characterized by UV-Vis,FT-IR and ¹H NMR spectroscopies along with electrochemical properties in this thesis.