P Toluidine, derivative

Primary aromatic amines give only the latter product, the structure of which was determined by X-ray crytallography for the p-toluidine-derived product 106 (83UP1). 

The sepMation of the production unit of mononitrotoluene from the next stages of nitration is desirable so as to provide the mononitration unit with a unit for removing m-nitrotoluene by distillation. A mixture of o and p- nitrotoluene or o- nitrotoluene alone is then used for further nitration. In the latter case p- nitrotoluene is utilized for the preparation of dyes (from p- toluidine, derivatives of stilbene, etc.) and pharmaceuticals (p- aminobenzoic acid.)... 

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 dilithio derivative of A-methanesulfinyl-p-toluidine (29) adds to aldehydes and ketones to give, after hydrolysis, the hydroxysulfinamides (30), which, upon heating, undergo stereospecifically syn eliminations to give alkenes. ° The reaction is thus a method for achieving the conversion RR CO — RR C=CH2 and represents an alternative to the Wittig reaction. ... 

The products from the reagent and alcohols depend on the nature of the alcohol. Primary alcohols yield the esters (202) from which several derivatives have been obtained. When the p-toluidine salts of (202) are heated in xylene, the phosphonamidodithioates (203) and the phosphonodiamidothioate (204) are formed. Tert-butyl alcohol presumably yields (202 R=CMe2) initially but at the reaction temperature butene is evolved... 

Aminohydroxyanthraquinone derivatives are available from leucoquinizarin by heating with an appropriate arylamine and boric acid in aqueous ethanol, followed by oxidation. The use of p-toluidine and subsequent sulphonation gives Cl Acid Violet 43 (6.37 X = OH). 

The thiazole ring system is found in many types of dye. Thiazole-containing sulphur dyes and primuline were considered in section 6.4-2. Quaternised dehydrothio-p-toluidine 6.133 is available as Cl Basic Yellow 1 (6.152). Other derivatives of this intermediate are used as direct dyes, such as Cl Direct Yellow 8 (4-58). The benzothiazole ring appears in various azo disperse dyes [14], quatemisation of which gives useful cationic dyes, an important example being Cl Basic Blue 41 (4.99). Another example containing a quaternised thiazole ring is Cl Basic Red 29 (4-102). 

Quinone is produced in small yield by direct oxidation of benzene itself with silver peroxide, but better by the action of oxidising agents on a large number of its p-disubstitution products. Thus, in addition to quinol, p-aminophenol (experiment, p. 176), p-anisidine, p-toluidine, and sulphanilic acid as well as p-phenylenediamine and many of its derivatives yield quinone in this way. 

Peroxidases, in particular CPO, catalyze the oxidation of aryl amines, e.g. p-toluidine, 3,4-dichloroaniline, 4-chloroaniline and 4-nitroaniline, by H2O2 to the corresponding nitroso derivatives (Eq. 11). 

The reaction of aromatic amines with tetrazine (151) gave either 1,2,4-triazoles (154) or pyrazolo[4,3-e]-l,2,4-triazines (155), depending on the substituents. While aniline, p-toluidine, p-anisidine and p-chloroaniline afford 155, the bromo and p-nitro derivatives give 154. Intermediates 152 and 153 were postulated (Scheme 22) (82CB683). 

The synthetic scheme for functionalized indolines shown in equation 83 assumes formation of a doubly metallated intermediate (335), derived from V,iV-diallyl-2,6-dibromo-p-toluidine, that may be quenched to the dehalogenated toluidine 336, or may undergo cyclization to 337. Quenching of 337 with trimethylchlorosilane in the presence of TMEDA leads to formation of indoline derivatives 338 and 339. Apparently a second cyclization of intermediate 337 to compound 340 is hard to accomplish . 

Tab. 10.6 summarizes the application of this transformation to a variety of racemic secondary allylic carbonates using the lithium anion of 4-methoxy-N-(p-toluidine)-benzene sulfonamide. The excellent regioselectivity obtained for this type of substitution provided an important advance in the synthesis of N-(arylsulfonyl)anihnes using the metal-catalyzed allyhc amination reaction. The allyhc alcohol derivatives examined... 

A quantitative correlation has been derived based on experimental data for 11 aromatic compounds (biphenyl, naphthalene, anthracene, phenanthrene, pyrene, phenol, p-toluidine, p-nitrotoluene, and o-, m-, and p-nitrophenol) at 20°C [74] ... 

In support of this view the p-amino-phenols themselves readily yield quinones. Also most p-substituted primary amines, e.g., p-diamines, p-alkylamines, such as p-toluidine, sulphanilic acid and its derivatives, behave similarly. In fact, the reaction can be used as a test for p-substi-tuted primary amines. p-Benzoquinone is usually made from aniline for the other p-quinones the p-amino-phenols, which are easily obtained by reduction of the p-nitroso-phenols and of azo-phenols, are employed. These reactions also apply, but not so widely, in the naphthalene series. 

In the above process only one-half of the amine is transformed into its benzoyl derivative. By working in presence of dilute caustic soda or other alkali (Schotten-Baumann Reaction, see benzoyl-p-toluidine), the amine is completely converted into its benzoyl derivative. 

Research by Zerweck et al. [2] suggests that many bake dyes contain thiazole rings. It was already known that dehydrothio-p-toluidine, which can be made by sulfur baking of />-toluidinc, and primulin bases, which are formed at higher temperatures, are both thiazole derivatives. 

Acetoacetic acid arylides and pyrazolone derivatives are the coupling components mainly used. Naphtbolsulfonic acids are of only minor importance here. Dehydrothio- p-toluidine sulfonic acid (2) and the sulfonated primulin base are also used as diazo components for certain orange disazo direct dyes. 

Substantive yellow monoazo dyes with very good light fastness are also obtained by oxidation of dehydrothio-p-toluidine and its derivatives. Oxidation of the sodium salt of the monosulfonic acid of the primulin base in the alkaline pH range with sodium hypochlorite results, for example, in C. I. Direct Yellow29, 19556 [6537-66-2] (22). 

For the preparation of biphenyl compounds with substituents in only one ring, it is usually advisable to employ a substituted aniline and couple with benzene rather than to use aniline and couple with a benzene derivative, since with benzene only a single biaryl compound is produced. Thus, 4-methylbiphenyl can be isolated readily in pure form from the reaction between diazotized p-toluidine and benzene, but not from the mixture of 2- and 4-methylbiphenyl formed from diazotized aniline and toluene. 

Azo compounds are formed to some extent in the biaryl reactions. From the reaction between diazotized p-toluidine and benzene, azo-p-toluene, CH3C6H4N=NC6H4CH3, was isolated, indicating that, in this particular instance at least, the azo compound was derived entirely from the diazonium compound. In addition to these types, of compounds, a considerable amount of high-boiling material is usually formed in the reactions. 

The new Reinecke-salt-like compounds K[Cr(NCS)4L ] (n = 1 or 2 L = o- or m-phenylenediamine, respectively) have been prepared by the reaction of K3[Cr-(NCS)6] with L and their thermal stabilities investigated.179 Diquinolino- and di-iodoquinolino-silver(i) iodide salts of the anions [Cr(NCS)6]3- and [Cr(NCS)4L2] (L = aniline, o- or p-toluidine) have been prepared and characterized.180 Chro-mium(m) thiocyanato-complexes with biguanide derivatives, K[Cr(NCS)4L] [L = phenyl-, p-chlorophenyl-, tolyl-, or 1-(p-chlorophenyl-5-isopropyl)biguanide], have been prepared by the reaction of K3[Cr(NCS)6] with L in anhydrous EtOH and their i.r. and electronic spectra reported.181 cis- and trans-[Cr(en)2(NH3XNCS)]2 + have been prepared and both shown to have a Amax value at 476 nm, but with the expected relative magnitudes of s values, cis > trans, as 120 to 80.182 The thermal decompositions of the salts [Cr(NH3)6 x(NCS)x](NCS)3 x (x = 0. 1. or 2) have been characterized. Under d.t.a. conditions [Cr(NH3)6](NCS)3 changes stepwise to [Cr(NH3)5(NCS)](NCS)2, trans-[Cr(NH3)4(NCS)2](NCS), and finally to merfac-[Cr(NH3)3(NCS)3].183... 

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