Reactions and characterisation of aromatic amines

Those reactions which are common to both aliphatic and aromatic amines and have been described under Aliphatic Amines (Section 111,123) will not be repeated in this Section except where difierences in experimental technique occur. 

Primary aromatic diamines cannot be diazotised (tetrazotised) and coupled normally. Thus o-ijhenylenediamine yields a triazole derivative and m-phenylenediamine gives an azo dye (Bismarck brown) by selfcoupling. 

Dissolve 1 g. of the secondary amine in 3-5 ml. of dilute hydrochlorio acid or of alcohol (in the latter case, add 1 ml. of concentrated hydro chloric acid). Cool to about 5° and add 4-5 ml. of 10 per cent, sodium nitrite solution, and allow to stand for 5 minutes. Add 10 ml. of water, transfer to a small separatory funnel and extract the oil with about 20 ml. of ether. Wash the ethereal extract successively with water, dilute sodium hydroxide solution and water. Remove the ether on a previously warmed water bath no flames should be present in the vicinity. Apply Liebermann s nitroso reaction to the residual oil or solid thus. Place 1 drop or 0 01-0-02 g. of the nitroso compound in a dry test-tube, add 0- 05 g. of phenol and warm together for 20 seconds cool, and add 1 ml. of concentrated sulphuric acid. An intense green (or greenish-blue) colouration will be developed, which changes to pale red upon pouring into 30-50 ml. of cold water the colour becomes deep blue or green upon adding excess of sodium hydroxide solution. 

Dissolve 1-0 g. of dimethylaniline in 10 ml. of dilute hydrochloric acid (1 1), cool to 0-5 , and slowly add, with stirring, a solution of 0-70 g. o sodium nitrite in 4 ml. of water. After 20-30 minutes, filter off the precipitated yellow hydrochloride, and wash it with a little dilute hydrochloric acid. Dissolve the precipitate in the minimum volume 

The p-nitroso compounds do not give Liebermann s nitroso reaction. 

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Primary aliphatic amines, 413 crystalline derivatives of, 424 reactions of, 420, 1072 table of, and derivatives of, 424 Primary aromatic amines, 539 crystalline derivatives of, 652 reactions and characterisation of, 648, 1073 ... 

Synthesis and characterisation of the first organometallic Tc(VIII) complex [MeTcOs] is described. Its reactions with alkenes and with aromatic amine bases are different to those of the analogous rhenium complex. 25 Terminal alkynes react with [Tc(Cl)(dppe)2] to form vinylidene complexes [Tc(=C=CHR)(Cl)(dppe)2] (R = Ph, Me, Bu ). Treatment of these complexes with acid yields the respective carbyne complexes [Tc( CH2R)(Cl)(dppe)2]. The Tc-C bond lengths in these complexes vary form 1.861(9) to 1.724(7) A, 26... 

Aromatic amines formed from the reduction of azo colorants in toy products were analysed by means of HPLC-PDA [703], Drews et al. [704] have applied HPLC/ELSD and UV/VIS detection for quantifying SFE and ASE extracts of butyl stearate finish on various commercial yarns. From the calibrated ELSD response the total extract (finish and polyester trimer) is obtained and from the UV/VIS response the trimer only. Representative SFE-ELSD/UV finish analysis data compare satisfactorily to their corresponding SFE gravimetric weight recovery results. GC, HPLC and SEC are also used for characterisation of low-MW compounds (e.g. curing agents, plasticisers, by-products of curing reactions) in epoxy resin adhesives. 

FD-MS is also an effective analytical method for direct analysis of many rubber and plastic additives. Lattimer and Welch [113,114] showed that FD-MS gives excellent molecular ion spectra for a variety of polymer additives, including rubber accelerators (dithiocar-bamates, guanidines, benzothiazyl, and thiuram derivatives), antioxidants (hindered phenols, aromatic amines), p-phcnylenediamine-based antiozonants, processing oils and phthalate plasticisers. Alkylphenol ethoxylate surfactants have been characterised by FD-MS [115]. Jack-son et al. [116] analysed some plastic additives (hindered phenol AOs and benzotriazole UVA) by FD-MS. Reaction products of a p-phenylenediaminc antiozonant and d.v-9-lricoscnc (a model olefin) were assessed by FD-MS [117],... 

P. 161.— The oxyindamines and oxyindophenols (Fast Blue, Gallocyanines, c.) are characterised by the ease with which they react with amines of the fatty and aromatic series, and certain compounds resulting from such reactions have appeared in commerce. 

The donor-acceptor complexes formed between electron acceptors (such as iodine or tetracyanoethylene) and electron donors (such as aliphatic amines or aromatic hydrocarbons) have, been extensively studied from various points of view -spectroscopic 5 structural and thermodynamic (3). Kinetic investigation has lagged behind, because the reactions are extremely fast and the equilibrium constants small the rate constant of one such reaction had been measured by means of our microwave apparatus (without the recent improvements), at -83 C (U). We have now determined rate constants, in 1-chlorobutane, as solvent for the reactions of zinc tetraphenyl-porphyrin with pyridine and 2-methyl pyridine, which have been well characterised by spectrophotometric methods (5, 6). They are less than the diffusion-controlled value by an order of magnitude. Further investigations are in progress. 

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