Metal/nitrogen displacement

Anion displacement of halides with azolyl anions is one common route to azolyl complexes. One example of such a synthesis is shown in Equation 4.21. In other cases, azolyl complexes have been prepared by proton transfer between the free azole and a metal alkox-ide or hydroxide. An example involving the synthesis of palladium-azolyl complexes is shown in Equation 4.22. In some rare cases, reactions of pyrrole and d early metal alkyls also lead to the formation of a metal-nitrogen bond via o-bond metathesis, as shown in Equation 4.23. Finally, several late-transition-metal-azolyl complexes possessing accompanying hydride Hgands have been prepared by N-H activation of pyrrole and other azoles. 

Nitrogen Displaces the Metal Phosphorus Displaces the Metal Oxygen Displaces the Metal Sulfur Displaces the Metal Fluorine Displaces the Metal Chlorine Displaces the Metal Bromine Displaces the Metal Iodine Displaces the Metal... 

Ni3C decomposition is included in this class on the basis of Doremieux s conclusion [669] that the slow step is the combination of carbon atoms on reactant surfaces. The reaction (543—613 K) obeyed first-order [eqn. (15)] kinetics. The rate was not significantly different in nitrogen and, unlike the hydrides and nitrides, the mobile lattice constituent was not volatilized but deposited as amorphous carbon. The mechanism suggested is that carbon diffuses from within the structure to a surface where combination occurs. When carbon concentration within the crystal has been decreased sufficiently, nuclei of nickel metal are formed and thereafter reaction proceeds through boundary displacement. 

Since potassium will burn in air, it is important to cut, slice, or powder the metal under an inert hydrocarbon solvent such as kerosene, toluene, or xylene. The air in the reaction flask should be displaced by an inert gas such as nitrogen. In this manner, fire hazard in handling potassium metal will be minimized. 

In the reaction flask is placed 600 cc. of commercial ter/.-butyl alcohol (Note 1), and the air in the flask is displaced by dry nitrogen gas. Then 29 g. (0.75 gram atom) of metallic potassium is added, in portions, to the alcohol. The mixture is heated on a water bath until all the potassium has dissolved, and then 68 g. (0.5 mole) of o-formotoluide (Note 2) is added and brought into solution. The condenser is set for distillation with a filter flask as the receiver this flask is protected from the air by connecting it to the trap used in the initial operation. The reaction flask is... 

A Cu(OAc)2-catalyzed intramolecular diamination of alkenes using sulfamide substrates such as compound 214 provides a route to fused thiadiazolidines 215 (Equation 48) <2005JA11250>. In this reaction, the transition metal activates the alkene toward nucleophilic attack by the first nitrogen, then becomes displaced by the second nitrogen nucleophile (a net M +z to M reduction). 

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