Aniline and nitrogen

The distribution of the isotopic label in the azide was deduced after degradation to aniline and ammonia (equation 118) 2ind to chloro-aniline and nitrogen (equation 119). 

HAZARD RISK Combustible when exposed to heat or flame decomposition emits toxic fumes of carbon dioxide, carbon monoxide, aniline and nitrogen oxides NFP A Code H 3 F 1 R0. 

Twofotms (l)(3olden-yellow leaflets or prisms from EtOH. M.p. 98 . Decomp. with slight explosion on sudden stroim heating. Sol. EtgO, C Hg. Mod. sol. hot EtOH. Insol. HgO, dil. min. aci<. Hot cone. Hd —> phenol, aniline, and nitrogen. Aniline hydroemoride —> p aminoazobenzene. (2) Yellow prisms. 

Nitrogen nucleophiles used to diplace the 3 -acetoxy group include substituted pyridines, quinolines, pyrimidines, triazoles, pyrazoles, azide, and even aniline and methylaniline if the pH is controlled at 7.5. Sulfur nucleophiles include aLkylthiols, thiosulfate, thio and dithio acids, carbamates and carbonates, thioureas, thioamides, and most importandy, from a biological viewpoint, heterocycHc thiols. The yields of the displacement reactions vary widely. Two general approaches for improving 3 -acetoxy displacement have been reported. One approach involves initial, or in situ conversion of the acetoxy moiety to a more facile leaving group. The other approach utilizes Lewis or Brmnsted acid activation (87). 

Migration to the developing electron sextet at nitrogen is not restricted to hydrogen. In (79) there is methyl migration with formation of methylamine and acetone in the acid-catalyzed decomposition of (80), phenyl migration leads to aniline and acetaldehyde. 

The effect of pH is rarely of use for pK measurement it is more often of use in identifying the site of protonation/deprotonation when several basic or acidic sites are present. Knowing the incremental substitutent effects Z of amino and ammonium groups on benzene ring shifts in aniline and in the anilinium ion (40), one can decide which of the nitrogen atoms is protonated in procaine hydrochloride (problem 24). 

As previously described, the Gould-Jacobs reaction has been applied to heterocycles fused to anilines, and to some amino-substituted heterocycles. Selectivity of N- and C-cyclization of 2-aminopyridino-methylene malonates has been mentioned (51 and 56). The normal mode of cyclization of 2-aminopyridino-methylene malonates is on the nitrogen to form a pyridopyrimidine. If an electron-donating group (EDG) is in the 6-... 

Several examples of nucleophilic displacement of nitro-activated leaving groups have been recorded. 5,6-Dinitrobenzofuroxan with aniline and p-bromoandine gives the corresponding substitution product (50). Azide ion displaces chloride from both 5-chloro-4-nitro- and 4-chloro-7-nitrobenzofuroxan (51 and 52) the product from the former loses nitrogen spontaneously to give furoxanobenzo-furoxan (benzobisfuroxan, 17), which is also formed, although in poor... 

By introducing reasonable values (about 2 for nitrogen, 4 for oxygen) for the electron affinity parameter relative to carbon, 8, and for the induced electron affinity for adjacent atoms (32/8i = Vio), we have shown that the calculated permanent charge distributions for pyridine, toluene, phenyltrimethylammonium ion, nitrobenzene, benzoic acid, benzaldehyde, acetophenone, benzo-nitrile, furan, thiophene, pyrrole, aniline, and phenol can be satisfactorily correlated qualitatively with the observed positions and rates of substitution. For naphthalene and the halogen benzenes this calculation does not lead to results... 

The literature on the hydrogenation of aniline and substituted anilines suggests that the amine functionality can act as a poison [3, 4, 12 and 13] especially over platinum catalysts. The more basic the nitrogen the more... 

Further, add 1 g. of dry finely powdered aniline hydrochloride to 5 g. of aniline and heat the mixture in a test tube on the water bath at 30°, with 2 g. of dry diazoaminobenzene. Continue heating the frequently stirred mixture for half an hour. Then raise the temperature to 45° and heat again for half an hour. When now a sample no longer evolves nitrogen on heating with hydrochloric acid, dissolve the aniline by adding 24 c.c. of 10 per cent hydrochloric acid (6 c.c. of concentrated acid and 18 c.c. of water). Recrystallise the aminoazobenzene hydrochloride, which remains undissolved, from 100 parts of hot water to which a little hydrochloric acid has been added. In order to obtain the orange-yellow base decompose the salt with sodium carbonate. 

Menshutkin reaction between jV,Ar-dimethyl-d6-aniline and methyl tosylate in nitrobenzene at 51.3°C (21) is consistent with an inductive KIE resulting from the increased electron density on the nitrogen (the nucleophilicity), a steric explanation was preferred for three reasons. 

A combination of column adsorption chromatography on basic alumina and GC of the eluate served for characterization of the trace fraction of nitrogen-containing compounds in hydroprocessed naphtha. These were subdivided into groups of four types, namely pyridines, pyrroles (the most abundant), anilines and indoles125. 

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