Reactivity Of α-Diimine Ligand Magnesium Compounds With Ketones

Since Cotton discovered the rhenium-rhenium quadruple bond in 1964,metal-metal-bonded compounds have developed rapidly in recent decades through the efforts of many scientists.Low-valent zinc–zinc bond,Cr–Cr quintuple bonds,Mo–Mo quadruple bonds,Mo–Mo quintuple bonds,and low-valent Mg-Mg-bonded compounds have reperted one after another.On the basis,the applications in the synthesis and catalysis field have been investigated for a long time.For example,Jones et al.used theβ-diimine Mg-Mg-bonded compound to successfully activate C-H bond,C-O bond,C-O bond,C-F bond,etc.,and can also be used as a catalyst to participate in the siliconitrile reaction.Mg-Mg-bonded compounds stabilized by different ligands,and their application scope has been expanded.This paper mainly explores the reactivity ofα-diimine ligand Mg-Mg-bonded compounds to small ketone molecules,and the synthesis method ofα-diimine ligand Mg-Mg-bonded compounds to small ketone molecules,and the synthesis method ofα-diimine ligand metal complexes with camphorquinone as the backbone.The full text is divided into three parts.1.The development history of metal-metal-bonded compounds is introduced.The synthesis and reactivity of Mg（Ⅰ）compounds stabilized by different ligands are introduce.In addition,the application of the metal compounds of camphorquinoneαdiimine ligands in the field of catalysis is briefly introduced.2.In this chapter,the reaction ofα-diimine Mg-Mg-bonded compounds with small ketone molecules was investigated.When reacts with 3-pentanone,small molecule occurrence form conversion and is inserted into Mg-Mg bond,the Mg-Mg-bonded is broken and bridged with the oxygen atom,and the H on theα-C of the small molecule migrates to the nitrogen atom of the ligand,the four-coordinated magnesium compound[μ-L¹（H）Mg（μ-OCH₂CH₃）CH₂CH₃)]₂（2）;with 2,4-dimethyl When reacts with 3-pentanone,the metal-metal-bonded is broken,the C=O double bond is reduced to a single bond,and the magnesium atom is connected to the oxygen end to form a four-coordinate magnesium compound[L¹Mg（μ-OCC（CH₃）₂CH（CH₃）₂）]（THF）K（3）.3.Study the synthesis thought of chiralα-diimine ligand metal compounds.First,The camphorquinoneα-diimine ligand was reduced by one equivalent of sodium to obtain a metal compound[L²Na（DME）]（4）which contains free radicals.The sodium and the two nitrogen atoms of the camphorquinoneα-diimine ligand were coordinated;Then,the zinc chloride complex was reduced with two equivalents of sodium to obtain a reduction product[L²Na₂（THF）₃]（5）in which two sodium ligands and three THF molecules were coordinated,wherein the ligands were negative divalent.Then,magnesium chloride was added to the divalent ligand and sodium to obtain a mononuclear magnesium complex[L²Mg（THF）₂]（6）,in which the metal magnesium is combined with the nitrogen atom of the ligand,and also coordinates with two solvent molecules.When camphorquinoneα-diimine ligand reacts with zinc chloride to obtain the zinc chloride complex[L²ZnCl₂]（7）,in which the zinc atom is coordinated with the nitrogen atom of the ligand.