Metal-nitrogen bonds, cleavage reactions

From Metal-Carbon and Metal-Nitrogen Bond Cleavage Reactions (J-3)... 

Though carbon-nitrogen bond cleavage reaction is less explored, allylic C-N bond can be cleaved by low valent late transition metal complexes. Treatment of (/x-dinitrogen or carbon dioxide)nickel(O) complexes with allylammonium... 

A variety of other reactions occur without metal-ligand bond cleavage. Reactions of this type have been used to convert nitrogen-containing ligands... 

The reaction appears to involve the nucleophilic attack by the amino-nitrogen on a sulphur atom of the S4N4 ring, leading to electrophilic cleavage of the metal-nitrogen bond (31). 

Without additives, radical formation is the main reaction in the manganese-catalyzed oxidation of alkenes and epoxide yields are poor. The heterolytic peroxide-bond-cleavage and therefore epoxide formation can be favored by using nitrogen heterocycles as cocatalysts (imidazoles, pyridines , tertiary amine Af-oxides ) acting as bases or as axial ligands on the metal catalyst. With the Mn-salen complex Mn-[AI,AI -ethylenebis(5,5 -dinitrosalicylideneaminato)], and in the presence of imidazole as cocatalyst and TBHP as oxidant, various alkenes could be epoxidized with yields between 6% and 90% (in some cases ionol was employed as additive), whereby the yields based on the amount of TBHP consumed were low (10-15%). Sterically hindered additives like 2,6-di-f-butylpyridine did not promote the epoxidation. 

The peculiar metal ion specificity of the ATP cleavage reaction may perhaps be explained by reference to some studies on the metal complexes of Schiff bases, which have provided clues to many aspects of biological metal catalysis. It was shown that metal ions will split the carbon-nitrogen double bond in thiophenalde-hyde-ethylenediamine (18, 21) as a consequence of the electronic-drift-to-metal... 

Reaction of the dimolybdenum nitrile complex 74 with Ru3(CO)i2 in refluxing toluene results in C=N bond cleavage to give the p4- and r5-nitrido clusters 75 and 76, respectively, in low yield. The metal geometry of 76 consists of a distorted bicapped square pyramid with a Ru atom spike, the nitrogen atom lying below the basal Mo2Ru2 plane.54... 

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