Nitrogen bonds formed

In Its overall design this procedure is similar to the Gabriel synthesis a nitrogen nude ophile IS used m a carbon-nitrogen bond forming operation and then converted to an ammo group m a subsequent transformation... 

Amines and amides undergo oxidation at or adjacent to nitrogen (Scheme 27). A neutral amine, for example, can be oxidized to afford a cation radical (117 to 116). Similarly, electrooxidation of the anion produced via deprotonation of a secondary amine leads to an aminyl radical (119) that is capable of participating in carbon-nitrogen bond-forming reactions with remotely tethered alkenes. 

Benzimidazoles bearing a halogen in the activated 2-position show a remarkable reactivity in palladium catalyzed carbon-nitrogen bond forming reactions. TV-protected 2-chlorobenzimidazoles reacted smoothly with a series of amines (6.81.). The activity of the aryl halide, besides the ready coupling of the chloro derivative, is also emphasized by the low catalyst loading used.112... 

Bipyridine was also en efficient ligand for the nickel-catalyzed carbon-nitrogen bond forming reactions. Using piperazine as a bifunctional amine, its monoarylation and diarylation were both achieved selectively with... 

Finally, a recently reported copper catalyzed carbon-nitrogen bond forming process utilises reagents with polarity opposite to the common disconnection protocols. An electrophilic nitrogen, in most cases an (9-acyl hydroxylamine derivative, was successfully coupled with diarylzinc reagents in the presence of copper triflate or copper chloride. Di(2 -pyridyl)zinc and TV-benzoyloxy-morpholine were reacted at ambient temperature in the presence of 1% copper(I) triflate to give 2-morpholinopyridine in 71% yield (7.81.), Under these mild conditions the reaction was over in less than one hour.103... 

Zwitterions in carbon-carbon and carbon-nitrogen bond-forming reactions as a promising synthetic strategy leading, in particular, to various heterocycles 06ACR520. 

Consecutive palladiumotalyzed carbon-nitrogen bond forming reactions can also be employed to access aromatic heterocycles. Nozaki has demonstrated this approach in the double N-arylation of 20 as a route to efficiently generate carbazoles (Scheme 6.40) [52]. This reaction can proceed with a range of alkyl and aryl amines, replacement of the aryl halides with sulfonates, and can even be performed consecutively to construct extended heteroacenes. 

As an alternative to primary amines in these double carbon-nitrogen bond forming reactions, Maes has demonstrated that 22 can undergo consecutive palladium-catalyzed carbon-nitrogen bond formation with orfho-dihalopyridine derivatives (Scheme 6.42). This reaction proceeds in good yield with a number of amidine variants, and provides a route to the construction of polycyclic imidazoles [54]. 

Palladium-catalyzed carbon-nitrogen bond forming reactions also provide an efficient route to generation of these precursors for Heck cyclization. Jorgensen... 

Carbon-Carbon and Carbon-Nitrogen Bond-Forming Reactions... 

This is the first example of a transition metal complex catalysed synthesis of compound 28, with a nitrogen-nitrogen bond forming reaction. Steric hindrance... 

Carbon - Nitrogen Bond Forming Reactions at Room Temperature... 

Sulfur - Nitrogen Bond Forming Reaction S-N bond 1... 

This experiment told us some new things about arginine and urea synthesis (a) that half of the nitrogen of the urea molecule originated specifically in aspartic acid, (b) that fumarate was a product of the reaction and (c) that phosphate bond energy, specifically in the form of ATP, was required for the new carbon to nitrogen bond formed. 

Carbon-Nitrogen Bond-Forming Process. Palladium-... 

SCHEME 1.6 Example of an asymmetric palladium-catalyzed carbon-nitrogen bond-forming reaction [18]. 

Sobota P, Trzebiantowska J, Janas Z (1976) Insertion of CO2 into the metal-nitrogen bond formed in the reaction with molecular nitrogen. J Oiganomet Chem 118(3) 253-258... 

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