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Toluidines, formation

Halogen Reactions. Hydrolysis of chlorotoluenes to cresols has been effected by aqueous sodium hydroxide. Both displacement and benzyne formation are involved (27,28). o-Chlorotoluene reacts with sodium in Hquid ammonia to afford a mixture of 67% of o-toluidine [95-53-4] and 33% of yW-toluidine [108-44-1], C H CIN, as shown in equation 3 (29). [Pg.53]

The reactivity of the 5-position of 2-aminothiophene in diazo coupling, which is present also in the acylated derivatives, complicates the formation of a diazonium salt from 2-aminothiophene. Thus Steinkopf and Miiller obtained only an azo dyestuff, although they proved, through the isolation of small amounts of 2-thienyl diazonium chloride, the diazotizability of 2-aminothiophene which had earlier been denied. However, recent Russian work claims the preparation of 2-thienyldiazonium chloride by treating the double salt in 10% hydrochloric acid with sodium nitrite. Amazingly high yields (over 90%) of azo compounds were then achieved by coupling the diazonium salt solution with y9-naphtol, w-toluidine or with the 2-aminothiophene double salt. These authors have also studied the... [Pg.85]

The lack of structural specificity among sedative-hypnotic drugs has been alluded to before. It is perhaps not too surprising that quinazolones, too, show this activity. The prototype, methaqualone (149), is obtained in a single step from the condensation of the"anthranilamide, 148, with o-toluidine.(The reaction may well involve first formation of the bisamide cycli-zation will then give the quinazolone ring system.) Condensation... [Pg.353]

A mixture of 4.0 grams of N-methyl-3-toluidine and 2.8 grams of sodium hydrogencarbon-ate in 50 cc of acetone was stirred at 0° to 10°C and 7.4 grams of 2-naphthyl chlorothiono-formate was added in small portions thereto and the mixture was heated under reflux for 30 minutes. The cooled mixture was poured into about 150 cc of cold water and 2-naphthvl-N-methvl-N-(3-tolyl)thionocarbamate was obtained as white crystals. Yield is 9.1 grams (90 o). Recrystallization from alcohol gave colorless needle crystals, MP 110.5° to 111.5°C. [Pg.1510]

However, is supercomplex 27 the true intermediate As previously mentioned, Sugasawa reported that reaction did not proceed with N,N-dialkyl anilines. Do N,N-dialkylanilines form a similar supercomplex We examined the following three anilines, ArNH2, ArNHMe, and ArNMe2, as shown in Figure 1.3. Under Sugasawa conditions at room temperature, formation of the corresponding supercomplex, respectively (29,30, and 31) was confirmed, based on their NMR analyses (Complex 29 and 31 were derived from toluidine and complex 30 comes from aniline). [Pg.13]

As the anhydride of nitrous and perchloric acids, it is a very powerful oxidant. Pinene explodes sharply acetone and ethanol ignite, then explode ether evolves gas, then explodes after a few s delay. Small amounts of primary aromatic amines-aniline, toluidines, xylidines, mesidine-ignite on contact, while larger amounts exploded dangerously, probably owing to rapid formation of diazonium perchlorates. Urea ignites on stirring with the perchlorate, (probably for a similar reason). [Pg.1384]

KPVS) and the indicator is usually o-toluidine blue (OTB). It is necessary for kx to be much larger than k2 (which is usually the case for poly electrolytes). If for example a cationic poly electrolyte together with OTB is titrated with KPVS, a polyelectrolyte complex is initially formed until no free polyelectrolyte is left to react with the KPVS. At this point, KPVS starts to react with OTB and a colour shift from light-blue to purplish-red indicates the end point. The titration relies upon the formation of a 1 1 complex, which is generally true provided that the ionic strength is low. [Pg.98]

The technical preparation of crystal violet and of its methyl-free parent substance, parafuchsine, almost the oldest of the triphenylmethane dyes, is not so easily explained. As is well known, in this process aniline and p-toluidine are united by oxidation in an acid melt. (In the preparation of fuchsine itself, which contains a methyl group attached to one of the benzene rings, o-toluidine is an additional ingredient.) Although all the phases of this important synthesis have not yet been experimentally established, we may nevertheless explain it on the basis of a dehydrogenation similar to that involved in the formation of malachite green. Moreover, the union of several molecules of base proceeds exactly according to the principle on which indamines are formed (p. 321) (Bucherer). [Pg.328]

Imidoyl chlorides of toluidines and naphthylamines were also applied (1886CB979). To avoid the formation of the disubstituted malonates, 2 mol of sodiomalonate was reacted with 1 mol of imidoyl chlorides (1886C B979). [Pg.5]

Catalysis by DABCO in the reactions of FDNB with piperidine, r-butylamine, aniline, p-anisidine and m-anisidine (usually interpreted as base catalysis as in Section B) was also assumed to occur by the formation of a complex between DABCO and the substrate14913. The high (negative) p-value of —4.88 was deemed inappropriate for the usually accepted mechanism of the base-catalysed step (reaction 1). For the reactions with p-chloroaniline, m- and p-anisidines and toluidines in benzene in the presence of DABCO a p-value of —2.86 was found for the observed catalysis by DABCO (fc3DABC0). The results were taken to imply that the transition state of the step catalysed by DABCO and that of the step catalysed by the nucleophile have similar requirements, and in both the nucleophilic (or basicity) power of the nucleophile is involved. This conclusion is in disagreement with the usual interpretation of the base-catalysed step. [Pg.1279]

Carbon tetrachloride. Chloroform, 2-Chlorophenol, Cyclohexanol, Cyclopentene, 1,1-Dichloroethylene, irans-l, 2-Dichloroethylene, IV.yV-Dimethylaniline, lV,lV-Dimethylformamide, 2,4-Dimethylphenol, 2,4-Dinitrotoluene, 1,4-Dioxane, 1,2-Diphenylhydrazine, Ethyl formate. Formaldehyde, Glycine, Methanol, Methylene chloride. Methyl formate, 2-Methvlphenol. Monuron, 4-Nitrophenol, Oxalic acid, Parathion, Pentachlorophenol, Phenol, l idine. Styrene, Trichloroethylene, Vinyl chloride Formylacetic acid, see cis-l,3-Dichloropropylene, irans-1,3-Dichloropropylene IV-Formylcarbamate of 1-naphthol, see Carbaryl Formyl chloride, see Chloroethane, Chloroform, sym-Dichloromethyl ether, ds-1,3-Dichloropropylene, irans-ES-Dichloropropylene, Methyl chloride. Methylene chloride. Trichloroethylene, Vinyl chloride lV-Formyl-4-chloro-o-toluidine, see Chlornhenamidine. [Pg.1530]

Methylformanilide, see p-Toluidine A-Methylformanilide, see A,lV-Dimethylaniline Methyl formate, see Bifenox... [Pg.1535]

A detailed investigation of aniline N-methylation on Cui xZnxFc204 was carried out through in situ FTIR spectroscopy. The reactants (aniline and methanol) and possible products (NMA, DMA and o-toluidine) were adsorbed on the catalysts and analyzed [106,107]. Adsorption of methanol indicated a dissociative chemisorption as methoxy species on catalyst surface at 100°C. As the temperature increased, oxidation of methoxy species to formaldehyde to dioxymethylene to formate species was observed, and above 300°C complete oxidation takes place to CO, CO2 and H2. Indeed methanol alone on Cui xZnxFc204 and Cui.xCoxFc204 behaves in a similar way [79,107]. [Pg.182]

Rhenium(V) 4-tolylimido complexes with the hydrotris(pyrazolyl)borate ligand, HB(pz)3, are formed on heating the 0x0 derivatives [ReOX2 HB(pz)3 ] (X = Cl, I) with 4-toluidine, whereas reactions with amines at ambient temperatures only give 0x0 complexes of the composition [ReO(NHR)Cl HB(pz)3 ]. The [Re(NC6H4-4-Me)X2 HB(pz)3] complexes react with ZnEt2 with formation of imido-ethyl complexes of the composition [Re(NC6H4-4-Me)Cl(Et) HB(pz)3 ]. " ... [Pg.328]

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 . [Pg.398]

Toxicology. ort/ o-Toluidine causes anoxia due to the formation of methemoglobin and hematuria xA-toluidine hydrochloride is carcinogenic in experimental animals. The meta-and para-isomers are assumed to produce comparable toxic effects however, meta-tolrriAine seems to have no carcinogenic activity. [Pg.686]


See other pages where Toluidines, formation is mentioned: [Pg.324]    [Pg.324]    [Pg.69]    [Pg.70]    [Pg.95]    [Pg.239]    [Pg.196]    [Pg.102]    [Pg.176]    [Pg.200]    [Pg.202]    [Pg.202]    [Pg.1512]    [Pg.243]    [Pg.334]    [Pg.121]    [Pg.116]    [Pg.384]    [Pg.82]    [Pg.873]    [Pg.345]    [Pg.167]    [Pg.171]    [Pg.181]    [Pg.935]    [Pg.952]    [Pg.120]    [Pg.107]    [Pg.1116]    [Pg.174]    [Pg.177]    [Pg.304]    [Pg.329]   
See also in sourсe #XX -- [ Pg.56 ]




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Toluidines

Toluidins

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