Compound aniline

Other derivatives of pyrrole that are of interest as coupling components are indole (12.39) and substituted indoles. Indole may be considered as a pyrrole with a benzo ring fused to it, or as a cyclized derivative of an 7V-monosubstituted aniline. For an aniline compound one expects either a C-coupling in the 5-position or an TV-cou-... 

Spectral data for the pentakis(trifluoromethyl)toluene, phenol and aniline compounds are also included in Scheme 5.52.4 It can be seen that these donor groups serve to deshield all of the trifluoromethyl groups but do so most effectively with the CF3 group that is para to it. 

A chloro-aromatic compound is to be converted to the corresponding aniline compound in a 1 m3 autoclave with a maximum allowed working pressure of 100 bar g. A large stoichiometric excess (4 1) of ammonia (30% in water) is used. This allows the neutralization of the resulting hydrochloric acid and maintaining an alkaline pH in order to avoid corrosion. The reaction reaches a conversion of 90% within 8 hours at 180 °C ... 

The constitution of these compounds is represented, according to the suggestion of Baeyer and Yilligcr,3 by an oxoninm formula with the halogen directly attached to quadrivalent oxygen, a suggestion supported by Blaise. The dimethyl-aniline compound is similarly represented ... 

Ammonophosphorous acids, nomenclature of, 2 265 Anatase, formation of, by 7-ti-tanium(IV) oxide, 6 82 Aniline, compound with thorium acetylacetonate, 2 215 5-Anilino-l,2,3,4-thiatriazole, 6 45 Anions, nomenclature of, 2 258 Antimony(III) cesium chloride, 2SbCl3-3CsCl, precipitation in extraction of cesium from pollu-cite, 4 6... 

Hartwig has reported a DPPF/Pd-catalyzed C-N coupling reaction between a diarylamine and an aryl nonaflate, Eq. (63) [64bj. The coupling below proceeded in 95 -100% yield (NMR) and was used in a strategy to prepare oligo(m-aniline) compounds. 

FIGURE 12.4 Enrichment factors for various aniline compounds with different pATa values and pHa= 0 (ar,= 1). (From Chimuka, L., Megersa, N., Norberg, J., Mathiasson, L., and Jdnsson, J.A., Ana/. Chem., 70, 3906, 1998. With permission.)... 

The piperidine compound (163 R, R" = —(CH2)j—) is easily hydrolyzed," and the aniline compound (163 R = Ph R" = H) cannot be prepared by this route. " A number of these compounds have been prepared by the alternative route 160a - 164 - 163." The reaction conditions were modified in more recent studies." Robertson identified 163 (R = 2-pyridyl R" = H) as the unexpected product of the reaction between 2-nitrophenylpropiolic acid and 2-aminopyridine. Further studies are needed to clarify these conflicting, and in some cases tentative, reports. The tautomerism of these compounds (163 R = aryl R" = H) is worthy of further study " (cf. Section II,A,4). Recently, a study of the tautomerism of the carbazide derivatives (165) has been made both tautomers (163, 165) were reportedly identified." ... 

The pH of the phosphate buffer as well as the percent acetonitrile in the mobile phase are the major factors affecting the separation of the anilines on the C-18 columns. By employing a low pH, the halogenated aniline compounds are separated not as the neutral free bases but as their corresponding anilinium ions. Thus the use of a lower pH buffer will decrease the elution time for all the compounds (74). 

The process of direct nitration of alkylated phenols was developed and implemented in the manufacturing plant. Later, the process was extended to nitration of phenol and several other alkylated phenols, substituted aniline compounds, and so on, by McDaniel and Gross. The process was implemented successfully to meet customer demand because of considerable reduction of in-process pollution streams, which could be treated in the plant treatment facihty with minimal plant modifications and ease of operation. The problems of treating and disposing of process wastes off-site were eliminated, making the process feasible compared to the DNBP process. 

The exact mechanism for intolerance to azo dyes and benzoates is still unknown. Since cross-reactions to various analgesics and anti-inflammatory drugs such as aspirin, indomethacin, dextropropoxyphene, phenylbutazone, menfenamate, ibu-profen, and sodium salicylate also occur, a nonallergic mechanism seems probable for most patients. A chemical resemblance can clearly be seen only between benzoates and salicylates (Fig. 1). When azo dyes are taken orally there will be an azo-reductive cleavage in the intestinal tract into sulfanilic acid and a pyrazolone derivative which can be further hydrolyzed to sulfophenylhydrazine (Ryan et al. 1969). Some azo dyes can form aniline compounds, which could explain their cross-reactions with preservatives (Walker 1970). 

A closely related reaction is the rearrangement of N-alkylamino-diaryl sulphides, which yield N-alkylphenothiazines on heating in boiling quinoline or aniline. Compound 17 was thus obtained from 16 (57% yield). 

Reserpine antagonism is also found in phenylthio analogues with ortho alkoxy or phenoxy groups, especially (48) [140,141]. In this series and also in analogous anilinomethyl morpholines, the SAR parallel those of the (46) series. The active aniline compounds are at least as potent as (46), the (48)-series are somewhat less potent [141]. 

Recently, however, a sclerodermatous syndrome with unusual features and visceral involvement has been reported following prolonged occupational exposure (32 years) to a wide variety of organic solvents (including benzene in various forms, toluenes, tolui-dines, xylenes, xylidenes, aniline compounds, and ethanolamine and its derivatives) (Bottomley et al. 1993). Associated functional changes include cold sensitivity, restrictive pulmonary disease, peripheral... 

Table 12.5 Oxidation potential of substituted aniline compounds...

Aliphat.. amides Thiols, Sulfides Glycols, Glycol ethers Alkyl chlorides Acid chlorides Phenols, Aryl ethers Aryl ketones Aromat. hydro- carbons Alkyl- benzenes Alkyl- anilines Compound types Mass values e... 

TABLE 1 Toxicity screening data from three sources used in this study, shown as exampie, for4-chloro-2-nitro-aniline (compound 28). 

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