Toluidine, properties

Physical properties. Majority are liquids except p toluidine and 1- and 2-naphthylamine. All are colourless when pure, but rapidly darken on exposure to air and light. All are very sparingly soluble in water, but dissolve readily in dilute mineral acids (except the naphthyl-amines, which are only moderately soluble in adds). They form colourless crystalline salts e.g., CjHjNH2,HCl) which are soluble in water these aqueous solutions usually have an add reaction owing to hydrolysis, and give the reactions of both the amine and the acid from which they are derived. Addition of alkali to the acid solution liberates the amine. 

The above simple experiments illustrate the more important properties of the anhydrides of aliphatic acids. For their characterisation, the reaction with aniline or p-toluidine is frequently employed. Alternatively, the anhydride may be hydrolysed with dilute alkali as detailed under Acid Chlorides, Section 111,88, and the resulting acid characterised as in Section 111,85. 

Cl Acid Gieen 25 [4403-90-1] (3) (Cl 61570) was also invented in 1894. This dye shows improved wetfastness, and is prepared from leucoquinizarin by reaction with 2 moles of i)-toluidine in a similat manner to the preparation of Cl Acid Violet 43 (134). Wetfastness and leveling properties may be altered by choosing the substituents of arylamines. The introduction of alkyl groups into aromatic amines improves the wetfastness and affinity in neutral or weekly acid baths. Examples ate Cl Acid Blue 80 [4474-24-27] (131) (Cl 61585) and Cl Acid Gieen 27 [6408-57-7] (132) (Cl 61580). 

Toluidine-blue prepared as above described presents the following characteristic properties It consists principally of the hydrochlorate of dimethyltoluthionine, the composition of which corresponds to the formula Ci5H,5N3S-HCI. 

Of a series of indanylthiocarbamates, to1 indate (2) had significant antifungal properties. It is prepared simply from 5-indanyl thionochloroformate (1) by reaction with N-methyl-m-toluidine. It presumably joins the fairly large family of organic compounds having sulfur divalently bound to carbon which are useful topical agents for dermatophytes. 

Table 8. Catalytic properties of zeolites studied in para-tolui-dine conversion. T . =400°C, para-toluidine benzene=1 4(mol), WHSV=1 h...

Chemical and physical properties of the pure substances ortAo-Toluidine... 

According to the submitters, other aromatic aldehydes and amines may be used in a similar manner with essentially the same yield of product. The exact procedure for isolation of the amine will depend upon its physical properties. Benzaldehyde and 0-toluidine yield o-tolylbenzylamine, m.p. 56-57° (hydrochloride, m.p. 165-166°), while />-tolylbenzylamine, obtained from />-toluidine, has a b.p. i62-i63°/5 mm. (hydrochloride, m.p. 181-182°). 

Humic substances (HS) were determined in water using catalytic cathodic stripping voltammetry (CSV).113 This method was based on the adsorptive properties of iron-HS complexes on the mercury drop electrode at natural pH. HS were also determined in water using a method based on the binding of a dye, Toluidine Blue (TB), to HS molecules to produce a dye-HS complex, which caused a decrease in absorbance at 630 nm.114 The method was rapid, sensitive, and practicable. 

D. Morineau, F. Casas, C. Alba-Simionesco, A. Grosman, M.-C. Bellisent-Funel and N. Ratovelomanana, A Neutron Scattering Investigation of the Structural Properties of Glassforming M-Toluidine Confined in MCM-41, J. Phys. IV10 (2000) pp. 95-98... 

These three toluidines have nearly the same properties, e.g., melting point and boiling point, but the aceto derivatives or acet-toluides, H3C—C6H4—NH—OC—CH3... 

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