Aniline PhNH

Photo-induced demethylation of 4-nitro-iV,A-dimethylaniline,to give 4-nitro-N-methylaniline, has been observed upon excitation in the presence of an external acceptor in benzene or the methoxide ion in methanol. A quantum chemical study of the photodissociation of the alkyl C-N bond in AT-substituted anilines, PhNH-R (R = Me, PhCH2, Ph2CH, Ph3C), has also been carried out. " ... 

There are two methods of converting aniline (PhNH ) to the final product. Alkylation is the direct method, but sometimes acylation followed by reduction gives better yields. This is because it is sometimes difficult to control the alkylation to only one alkyl group. 

Cyclization of hydrazonyl chloride 797 with aniline gave triazolotriazine 798 (R2 = PhNH) (80JHC209). Cyclization of 797 was also effected by the action of sodium acetate to give 798 (R2 = Cl) (83JHC285). Cyclization of 799 by the action of sulfuric acid gave a triazolotriazine formulated as 800 or 801 (83JHC285). 

An X-ray analysis has confirmed the structure of the product (39) formed when 2-aminobenzamide is heated with P S q in pyridine (there is no reaction in toluene). In the presence of alkali, dimethyl sulphate converts (39) into (40 R=SMe) which, in turn, yields (40 R=C HgN or PhNH) by reaction with pyrrolidine or aniline. 

In order to understand these results it is necessary to consider the nature of the intermediates formed upon photolysis of arylamines. The absorption spectra of transients produced upon photolysis of aniline and various alkyl ring-substituted arylamines was obtained by Land and Porter (18) in different solvents using a flash photolysis apparatus. On this basis they identified both an anilinyl radical (PhNH-) and an anilinyl radical cation (PhNHj). The radical cation is present in polar media (H2O) but absent in cyclohexane. From these results, a homolytic cleavage... 

The imide (86) (see (16a) in Section 4.06.5.2) is a reactive acylating reagent under mild conditions. Reaction with aniline or phenol yields diphenylurea (PhNH)2CO or diphenyl carbonate (PhO)2CO respectively. With benzoic acid, 2-phenyl-4-benzoyl-l,3,4-oxadiazoline-5-thione is formed, hence reaction of (86) with benzoic acid and nucleophiles NuH (Nu = NHPh, OPh, SPh) yields amide PhCONHPh, ester PhC02Ph, and thioester PhCOSPh respectively. With diamines R(NH2)2, (86) forms polyureas [-CONHRNH-] <89BCJ539>. 

Historically the first fully unsaturated azepine was obtained by Wolff in 1912 by the decomposition of phenyl azide in aniline. However, the actual structure of this product, named dibenzamil , remained unknown until 1955, when Huisgen and coworkers showed it to be an anilinoazepine, originally formulated as the 7-anilino-2H-azepine, but later corrected, mainly on the basis of HNMR evidence, to the 2-anilino 3H-tautomer (221 R1=PhNH R2 = H). Subsequently, the thermolysis and photolysis of aryl azides in primary, secondary and, in certain instances, tertiary amine solution has become a standard method for the preparation of 2-amino-3/f-azepines (79AG(E)900,8lAHC(28)23l). 

Conditions were found under which 2,4,6-trinitrostyrene adds nucleophiles (thio-phenol, aniline, and aliphatic amines) at the vinyl moiety to form the corresponding / -X-ethyl-2,4,6-trinitrobenzenes (X = PhS, PhNH, or R2N). In the reactions with primary aromatic amines, the initially formed adducts undergo an intramolecular replacement of the nitro group followed by aromatization of the indolines, giving rise to the corresponding A-substi Luted 4,6-dinitroindoles.219... 

It is not possible to construct an invariant nucleophilicity order because different substrates and different conditions lead to different orders of nucleophilicity, but an overall approximate order is NH2 > PhaC > PhNH (aryne mechanism) > ArS > RO > R2NH > ArO > OH > ArNHi > NH3 > 1 > Br > Cl > H2O > ROH. As with aliphatic nucleophilic substitution, nucleophilicity is generally dependent on base strength and nucleophilicity increases as the attacking atom moves down a column of the periodic table, but there are some surprising exceptions, for example, OH, a stronger base than ArO , is a poorer nucleophile. In a series of similar nucleophiles, such as substituted anilines, nucleophilicity is correlated with base strength. Oddly, the cyanide ion is not a nucleophile for aromatic systems, except for sulfonic acid salts and in the von Richter (13-30) and Rosenmund-von Braun (13-8) reactions, which are special cases. 

For decades, the only BDE(N—H) value known was that of the ANI radical cation in aqueous solution179. In a 1982 review, only seven values were reported including the values of 368 and 366 kJmol-1 for PhNH—H and PhMeN—H, respectively180. In 1991, two more BDE values were determined181, namely 386 kJmol-1 for PhNH—H and 366 klmol-1 for Ph2N—H. Since then, both experimental and theoretical results for BDE(N—H) of several series of aniline derivatives have been available182-198. 

Aminolysis of POCl3 with N-methyl- and N-ethyl-aniline has been reexamined to show that, contrary to earlier reports, the products are (PhRN)2(PhNH)PO, where R = Me or Et.342 Improved syntheses and definitive physical data have been given for a number of alkoxymethyl-phos-phonic and -phosphonothioic derivatives, including ROCH2P(X)Cl2 and ROCH2P(X)Cl(OEt), where X-Oor S.343... 

The nitrosyl chloride adduct of cyclohexene (as the a-chlorooxime) condenses with sodium or potassium cyanide in dimethyl sulfoxide (or ethanol) to yield 3-amino-4,5,6,7-tetrahydroanthranil (185 R = NH2).265-266 Cycli-zation of the oximinothioamide 187 with alkoxide proceeds via loss of SH to give the 3-anilinotetrahydroanthranil (185 R = PhNH). In methanolic hydrogen chloride, however, aniline is eliminated and the unstable 4,5,6,7-tetrahydroanthranil-3-thiol (185 R = SH) is produced in 30% yield.267... 

Full details have now been given of the preparation and characterization of phenylaminophosphines, e.g., (PhNH)3P, from the reaction of dialkylamino-phosphines with aniline, The new atropisomeric chiral diphosphine (72) has been prepared by the reaction of chlorodiphenylphosphine with the appropriate 2,2 -diaminobiphenyl. Related reactions of alcohols and aminoalcohols with chlorodiphenylphosphine have led to several new ligand systems,including the chiral molecules (73) and (74). ... 

The complex ions cA-[Co(en)2LCl] + with L = aniline or m-toluidine have both been shown readily to lose a proton to form their respective conjugate bases (L = PhNH" or /M-MeCsHjNH-), and rate data for chloride-ion aquation are reported for all four species (Table 3). Above pH 3 significant concentrations of these coryugate bases are present since the equilibrium formation constants are ca. 10 . The enhanced reactivity of the conjugate bases is in line with the now well established S Nlcb mechanism for base hydrolysis. 

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