Breaking C-N Bonds

The presence of different catalytic sites for the first C-N bond breaking of DHQ and the hydrogenation of CHE is confirmed by the -ln(l-XDiKj) versus -ln(l-X(niK) plot. In the simultaneous reactions of A and B, in which A and B are both adsorbed on the same catalytic site and follow a Langmvtir-Hinshelwood mechanism, we have... 

The most important C-N bond breaking reaction is the hydrogenolysis of the carbon-nitrogen O-bond. 

TIL Fife, Kinetic and Mechanistic Effects of Ease of C-N-Bond Breaking in Amide Hydrolysis, The... 

Even more surprising is the finding that the reactivity picture exhibited by the various ethoxide species in the ethanolysis of phenyl acetate is very similar to that found in the ethanolysis of the activated amide N-methyl-2,2,2-trifluoroacetanilide [Eq. (3)], despite the different mechanisms of the two reactions [13]. Schowen ef al. [14] showed that C-N bond breaking in the rate-limiting decomposition of the tetrahedral intermediate is assisted by proton transfer from a general acid to the leaving group. 

Under flash vacuum thermolysis (FVT) the 1,2,3-triazine (32) was readily thermolyzed to an alkyne, a nitrile, and nitrogen in high yields. For unsymmetrically substituted 1,2,3-triazines as FVT substrates, fragmentation proceeded selectively a bulky substituent at C-4(6) made the adjacent C—N bond break more easily than the opposite C—N bond. The FVT method was applied to the synthesis of the fluorinated alkynes, perfluoro-3-methyl-l-butyne and difluoroethyne [(33), R = (CF3)2CF, F] (Equation (1)) (89CC1657, 91CC456). It has been claimed, however, that tris(dimethylamino)-1,2,3-triazine forms the monocyclic azete. 

As shown by Eq. (5-61), the dipolarity of the solvated reactant molecule decreases during the activation process. Loss of nitrogen by simultaneous C—N bond-breaking produces a 1,4-biradical. 

C—N bond cleavage (propagation) is favoured by the ring strain and one antiperiplanar orbital at oxygen atom. The exocyclic C—N bond breaks in the depropagation step ... 

In batch experiments in an autoclave hdn of pyrrole, indole, and carba-zole, over sulphided Co-Mo, Ni-Mo, Re, and Co-Re catalysts supported on AI2O3 was first order in reactants and proceeded by consecutive steps. C-N bond breaking was rate limiting. Rate constants for the overall reactions and for each step are given. 

Data for the CNH reaction of indole over the same catalysts are displayed in Fig. S (CNH refers to the first C-N bond-breaking step forming o-ethyl aniline, e.g. the disappearance of... 

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