1,2-diaza-4-phospholide Complexes Of Cobalt(Ⅱ) And Chromium(Ⅱ):Synthesis,Structural Characterization,and Magnetic Susceptibility

The monoanionic 1,2-diaza-4-phospholides（[3,5-R₂dp]^-,R=Ph,t Bu）can be either oxidized by high-valent metal ions or reduced by alkali metals.Because of their unique electronic structures,the complexes with 1,2-diaza-4-phospholides may present unique physical and chemical properties.In particular,the corresponding 3d transition metal complexes are highly expected to behave as SMMs（single-molecule magnets）which could be used in the fields of information storage materials and organic catalysis.In this paper,we used 1,2-diaza-4-phospholide monoanions with different substituents as ligands to coordinate with 3d metal ions cobalt（II）and chromium（II）.Our work showed that seven metal organometallic compounds,including five cobalt and two chromium nitrogen-phosphorous heterocyclic metal complexes,have been prepared.All of the products were fully characterized by X-ray single crystal structure analysis,IR,melting point,magnetism,and cyclic voltammetry.The main points of thesis were summarized as below:1.Complexes{[Li₄O₂（3,5-t Bu₂dp）₄][Cp Me₅Co Cp Me₅]}（1）,{[Cl₂Co₂Li₂O（3,5-t Bu₂dp）₄][Cp Me₅Co Cp Me₅]}（2）were obtained by the reaction of3,5-disubstituted-1,2-diaza-4-phospholides with Cp Me₅Li and cobalt dichloride at molar ratio of 1:1:1.2.Heterobimetallic complex[（η⁵-Cp Me₅）Co^II{η¹（N）,η¹（N）-3,5-Ph₂dp}₂(μ₂-Li（THF）]（3）,tetranuclear complexes[（η⁵-Cp Me₅）Co ^II{η¹（N）,η¹（P）-3,5-Ph₂dp}]₄（4）and[（η⁵-Cp Me₅）₄Co^II{η¹（N）,η¹（P）-3,5-Ph₂dp}₂Co^III{η¹（N）,η¹（P）,η¹（C）-3,5-Ph₂dp}₂]（5）with solid state grids were prepared by the reaction of 3,5-di-phenyl-1,2-diaza-4-phospholides with Cp Me₅Li and cobalt dichloride at molar ratio of 1:1:1.3.Heterobimetallic complexes[（η⁵-Cp Me₅）Cr^II{η¹（N）,η¹（N）-3,5-Ph₂dp}₂(μ₂-Li（TH F）]（6）,[（η⁵-Cp Me₅）Cr ^II{η¹（N）,η¹（N）-3,5-Ph₂dp}₂（μ₂-Li（THF）₂）]（7）were synthesized by the reaction of 3,5-di-phenyl-1,2-diaza-4-phospholides with Cp Me₅Li and chromium dichloride at molar ratio of 1:1:1.