Carbon-nitrogen bonds compounds

It is of interest that antibacterial activity can be retained even when the imine carbon-nitrogen bond is replaced by a carbon to carbon double bond. Base-catalyzed condensation of 5-nitrofurfuraldehyde (24) with 2,6-dimethylpyridine (38) affords olefin 39. Treatment of this compound with hydrogen peroxide gives the corresponding N-oxide (40). Heating of... 

Dithiophosphoric and dithiophosphinic acids can also react with organic compounds containing multiple carbon-nitrogen bonds, often under very mild conditions, to give thioamides and other related compounds (e.g., Equation 82).163... 

Carbon-Nitrogen Bond Formation The cathodic reduction, in protic media, of aromatic nitro compounds produces nucleophilic centers, either... 

The cyclizahon of amino alcohols should be an attractive method for the synthesis of N-heterocyclic compounds, mainly because they can be obtained in a single step and without the generation of wasteful byproducts. Carbon-nitrogen bond formation catalyzed by Cp lr complexes has been extended to the synthesis of N-hetero-cyclic compounds by the cyclization of amino alcohols. 

Cleavage of carbon-nitrogen bonds is also important in synthetic and, sometimes, biomedical ion-radical chemistry. Thus, triazenes are regarded as carcinogenic compounds. Speiser and Stahl (1992) showed that the benzenediazene cation-radicals easily eliminate -N=N- fragment together with an unpaired electron. 

The stability of polynitroaliphatic compounds to acids, bases and nucleophiles is often linked to the presence of an acidic o -proton(s) which may allow various resonance structures to lead to rearrangement or decomposition. Additionally, the presence of two or more nitro groups on the same carbon atom greatly increases the susceptibility of the carbon-nitrogen bonds to nucleophilic attack. 

Cleavage of the carbon-nitrogen bond occurs in benzyloxycarbon amino compounds as a result of decarboxylation of the corresponding free carbamic acids resulting from hydrogenolysis of benzyl residues [725, 729, 7S0] (p. 151). 

Carbon-nitrogen bond formation, by reductive amination, 59, 1 Carbon-phosphorus bond formation, 36, 2 Carbonyl compounds, addition of... 

Most cyclizations described in this chapter involve a carbon-nitrogen bond as the final step. However, the A -amino compound 17 offers an example of a carbon-carbon bond formation to complete ring formation. Treatment of 17 with MeCOCH2COMe gives a mixture of products 18 and 19 (Equation 6) <2003CHE953>, with 19 obtained in very small amounts. 

Nitrogen (ca. 5 at. %) occurs as carbon-nitrogen bonds, probably mainly cyanamide (NCN ), although other C-N bonded compounds were also believed to be present. If cyanamide is present as the Cd salt, this would tie up 5% of the Cd. The Cd S ratio was found to be only slightly higher than unity (ca. 1.02), and some of the Cd may be bound to carbonate. Therefore other C-N species are likely also to be present, e.g., cyanide, several of which could adsorb to one Cd or even to a CdS moiety. By reducing the concentration of thiourea in the bath, C-N impurities in the CdS film could be reduced almost to zero [77]. Whatever the nature of the C-N impurity, much of it could be removed simply by dissolution in water at 60°C [78]... 

Nitro-compounds fRNOj) are isomeric with nitrites, but their electronic structure, excited states and photochemistry are very different. There is no very low-lying (n.jt ) state, and nitroalkanes show n — 3i absorption with a maximum around 275 nm ( —201 mol - cm In cyclohexane solution, nitromethane (CH1NOi) is photoreduced to nitrosomethane(CH,NO, but nitroethane under the same conditions gives rise to a nitroso-dimer derived from the solvent CS.47). The latter process is probably initiated by cleavage of the carbon-nitrogen bond in the nitroalkane. In basic solution (when the nitroalkane is converted to a nitronate anion) irradiation can lead to efficient formation of a hydroxamic acid (S.48), and this reaction most likely proceeds through formation of an intermediate three-mem bered cyclic species. 

EMDE DEGRADATION. Modification of the Hofmann degradation method for reductive cleavage of the carbon-nitrogen bond by treatment of an alcoholic or aqueous solution of a quaternary ammonium halide with sodium amalgam. Also used as a catalytic method with palladium and platinum catalysts. The method succeeds with ring compounds not degraded by the Hofmann procedure. 

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