Arylated anilines hydrocarbons

III. ARYLATED ANILINES AND RELATED SPECIES A. Amino Derivatives of Polynuclear Aromatic Hydrocarbons... 

Although not strictly an arylated aniline but rather a benzannelated species, the two isomeric naphthylamines are the simplest polynuclear aromatic hydrocarbon counterparts of aniline. Unfortunately, they are the only such examples with enthalpy of formation data known to the authors. No less than five sets of measurements23,44 - 47 with a range of 29 kJmol-1 have been reported for the enthalpy of combustion, and thus of formation, of 1-naphthylamine. Likewise, for the enthalpy of combustion of 2-naphthylamine... 

If, instead of a palladium catalyst, a nickel catalyst, such as the bipyridylnickel(II) bromide, is used for the arylation of amines (Fig. 7), the reduction of the aryl halide into the corresponding aromatic hydrocarbon is still present for the primary or secondary benzylamines but, the arylation into substituted anilines is the main reaction even most often the only one, for the other types of amines. 

Carbanions from hydrocarbons, nitriles, ketones, esters, TV./V-dialkyl acetamides and thioamides, and mono and dianions from (3-dicarbonyl compounds are some of the most common nucleophiles through which a new C-C bond can be formed. This C-C bond formation is also achieved by reaction with aromatic alkoxides. Among the nitrogen nucleophiles known to react are amide ions to form anilines however, the anions from aromatic amines, pyrroles, diazoles and triazoles, react with aromatic substrates to afford C-arylation. 

Consensus on nomenclature had been reached by the 1890s. Aniline was the parent of its derivatives, though sulfonic acids were considered derivatives of benzene, such as aminobenzenesulfonic acid. The prefix amino- was added to naphthalene and its derivatives. Many trivial names came into use, particularly for aminonaphthalenesulfonic acids, found in both academic and industrial research laboratories. Though IUPAC convention now numbers amino aryl compounds according to the parent hydrocarbon, the earlier system of numbering has often been retained, since some names include the positions of substituents at carbon atoms numbered according to the older systems. 

The hydrolysis of aniline to phenol in supercritical water by Patat [5] is accredited as the earliest reported study of a simple reaction in a supercritical medium. The reaction is catalysed by hydrogen ions formed from dissociation of phosphoric acid. Close to the critical point of water the catalyst has limited solubility, but as the conditions of the flow reactor were raised towards 450°C and 710 bar, the reaction rate was observed to increase by an order of magnitude. The mechanism was unaffected by the phase change it was from the better contact between reactants and catalyst that the rate improvement was derived. Townsend has taken advantage of homogeneity to study the reaction of a series of coal model compounds (alkyl-aryl hydrocarbons and ethers) in supercritical water [6]. For the hydrocarbons a free-radical pyrolysis route does not take advantage of the medium. However, for the ethers enhanced rates of reaction through a hydrolysis route occurs. 

---