M-Phenylenediamine

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

The pyromellitic dianhydride is itself obtained by vapour phase oxidation of durene (1,2,4,5-tetramethylbenzene), using a supported vanadium oxide catalyst. A number of amines have been investigated and it has been found that certain aromatic amines give polymers with a high degree of oxidative and thermal stability. Such amines include m-phenylenediamine, benzidine and di-(4-amino-phenyl) ether, the last of these being employed in the manufacture of Kapton (Du Pont). The structure of this material is shown in Figure 18.36. 

Toluene-2,4-diammonium sulphate (4-methyl-m-phenylenediamine sulphate) o-Toluidine... 

The parent system 3 was reported fw the first time as a product obtained in low yield originating from the vapor-phase cyclodehydrogenaticMi of /V,/V -diphenyl-m-phenylenediamine (137) over a platinum-on-magnesium catalyst (Scheme 17) (61JOC1509). 

Another short protocol for preparation of 3 was recently presented by Knolker and Reddy, who devised a short sequence involving a double iron-mediated arylamine cyclization as the key step (Scheme 19). Thus, the reaction of m-phenylenediamine (140) with the tricarbonyliron-complexed cyclohexadienyl cation 141 yielded the complex 142, which was eventually transformed into indolo-[2,3-()]carbazole (3) via cyclization and dehydrogenation (98TL4007 00T4733). 

Trinitro-m- phenylenediamine > 60cm > 24cm > 60cm > 24cm... 

Example 15. PA from m-phenylenediamine and adipoyl chloride by solution polymerization.2 32 To a well-dried 250-mL three-necked straight-wall flange flask with nitrogen inlet/outlet, dropping funnel, and magnetic stirrer (Fig. 3.18b),... 

This polymer can be synthesized from m-phenylenediamine and isophthaloyl chloride. It can be prepared by interfacial polymerization or solution polymerization.4,7 9 14... 

The reactivity of T8[OSiMe2H]g is dominated by its capacity to undergo hydrosilylation reactions with a wide variety of vinyl and allyl derivatives (Figure 30) that have subsequently mainly been used as precursors to polymers and nanocomposites by the introduction of reactive terminating functions as shown in Table 19. For example, T8[OSiMe2H]g has been modified with allyglycidyl ether, epoxy-5-hexene, and 1,2-cyclohexene-epoxide to give epoxy-terminated FOSS. These have then been treated with m-phenylenediamine, with polyamic acids or... 

The scope and mechanism of the isomerization of arylamines to methyl-substituted aromatic heterocycles have been studied. Aniline, toluidines, naphthylamines and m-phenylenediamine all gave the corresponding ortho-methyl-substituted aza-aromatics when exposed to high NHj pressure and elevated temperature in the presence of acid catalysts, e.g., zeolites. The yiel of pyridines formed by this process range from low to moderate <95JC(155)268>. 

A range of products was obtained from aniline including those from oxidative coupling (azozybenzene, azobenzene, and benzidine), and phenazine by dimerization (Chan and Larson 1991). Oxidation of m-phenylenediamine was initiated by the oxidation of two molecules to produce an A-phenyl-2-aminoquinone-imine that reacted with m-phenylenediamine to produce 2-amino-5-phenylaminoquinone-imine after further oxidation (Kami et al. 2000). 

The use of hydrogen peroxide in conjunction with Fe(II) (Fenton s reagent) or ozone has already been noted. It has been nsed alone to examine the products from o - and m-phenylenediamines in the context of their mntagenicity (Watanabe et al. 1989). Successive reactions produced 3,4-diaminophenazine from o-phenylenediamine, and 3,7-diaminophenazine from m-phenylenediamine. 

Kami H, T Watanabe, S Takemura, Y Kameda, T Hirayama (2000) isolation and chemical-structural identification of a novel aromatic amine mutagen in an ozonized solution of m-phenylenediamine. Chem Res Toxicol 13 165-169. 

Watanabe T, T Hirayama, S Fukui (1989) Phenazine derivatives as the mutagenic reaction product from o- or m-phenylenediamine derivatives with hydrogen peroxide. Mutation Res 227 135-145. 

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