M-Tolidine

Tedmical Observations. The manufacture of benzidine is one of the most important operations of dye chemistry, because this base is used in the preparation of numerous valuable, although generalty unstable, direct dyes. Similar methods are used to prepare the tolidines (ortho and meta) from o- and m-nitrotoluenes, and o-dianisidine from o-nitroanisole. Dyes from m-tolidine will rare go on cotton, but they are interesting wool dyes. 

H2SO4 forms salts (Ref 3, p97) 4,4 Diamino-2,2 dimethyldiphenyl 2,2 -Dimethylbenzidine or m-Tolidine,... 

Robinson C and Mills HAT, The Colloid Chemistry of Dyes The Aqueous Solutions of Benzopurpurine 4B and its Isomer Prepared From m-Tolidine. Part I, Proc. Roy. Soc.. 1931,131A, 576. 

Diamino -2 2 - dixnethyldipbenyl (4 4 -Diom no-2 2 -dUoljfi, pp -diowitno-oo -at-tolyl, m-tolidine)... 

Multi-functionalized Polyimides. As shown in Scheme 3, the polyimides containing pendant N-acylated caprolactam moieties were prepared by the two-step polycondensation of BAPBC with commercial dianhydrides. A polyamic acid (PAA) viscous solution was formed by stirring equimolar amounts of the derivatized diamine with the dianhydride in NMP at room temperature. The subsequent chemical imidization was carried out by adding pyridine and acetic anhydride to the PAA solution to produce the multi-functional polyimide. The amount of pendant groups incorporated and the rigidity of the polyimide chains were varied by copolymerizations with non-derivatized diamines such as o-tolidine (OTOL), m-tolidine (MTOL), or 2,2 -bis(trifluoro methyl)benzidine (PFMB). The incorporation of the N-acylated caprolactam moieties in the polyimide chains was confirmed by the FTIR absorptions at 2931 and 2864 cm (Uas and CH2 in pendant acylated caprolactam moieties) as well as the absorptions at 1778 and 1727 cm (v s and Vg, C=0 in imide ring). 

Z)-Tolidine (3,3 -dimethylbenzidine) [119-93-7] M 212.3, m 131-132", pK 4.45. Dissolved in benzene, percolated through a column of activated alumina and crystd from benzene/pet ether. 

One run was made using 27 g. of Eastman s practical o-tolidine, m.p. 121-125°. The procedure employed differed from the above only in that the benzene solution was washed once with 40 cc. of 10 per cent aqueous alkali. There was obtained 18.9 g. (82 per cent of the theoretical amount) of a light... 

Dimethylbiphenyl can be prepared from w-bromotoluene8 or m-iodotoluene9 and sodium by the action of copper powder on w-iodotoluene 10 by treating 4,4 -dihydroxy-3,3/-dimethyl-biphenyl with zinc dust 11 by heating 4,4,-dichloro-3,3,-dimethyl-biphenyl with hydriodic acid and phosphorus 11 by treating o-tolidine with nitrous acid in alcoholic solution 12 by the decomposition of tetrazotized o-tolidine with methanol or ethanol... 

Figure 3.16 (A) Spectra recorded during spectropotentiostatic experiment in optically transparent thin-layer electrode on 0.97 mM o-tolidine, 0.5 M acetic acid, 1.0 M HC104. Applied potentials A, 800 B, 660 C, 640 D, 620 E, 600 F, 580 G, 400 mV vs. SCE. (B) Nernst plot at 438 nm. [From Ref. 36.]...

The oxidizing properties of chlorate are utilized in its spectrophotometric determination. Chlorate admixtures in perchlorates have been determined by its colour reaction with benzidine [44] and J(5-thiosemicarbazone dimedone (e= 1.910 at 417 nm) [45]. Chlorate in water has been determined with o-tolidine [46]. At a suitably high chloride concentration in 3-7 M H2SO4, chlorate reacts quantitatively with Cf to form CI2, which decreases the absorbance of Methyl Orange [47]. 

Figure 17.1.3 Responses at a 2000 wire-per-inch gold minigrid during a double potential step experiment. The solution contained 0.8 mM o-tolidine in 1 M HCIO4-O.5 M acetic acid. In the forward step a-tohdine was oxidized in a diffusion-controlled, two-electron process. The stable product was...

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