Of aromatic amines

Fischer-Hepp rearrangement The nitros-amines of aromatic secondary amines when treated with hydrochloric acid give nuclear substituted nitrosoamines. Among the benzene derivatives, if the para position is free the -NO group displaces the hydrogen atom there in naphthalene derivatives it enters the 1-position ... 

Amination of Aromatic Heterocyclic Lactam Systems (Synthesis of Cytidines)... 

Unfortunately, the two fuU papers on the silylation-amination of pyrimidine [49] and purine nucleosides [64] as discussed in Sections 4.2.3 and 4.2.4, were pubhshed in German and are thus not readily accessible, although a few detailed procedures from Sections 4.2.3 and 4.2.4 were subsequently published in English [65]. The third paper on the silylation-amination of aromatic hydroxy-N-hetero-cycles, however, as discussed in Section 4.2.5 was, fortunately, pubhshed in English [27]. 

The amination of aromatic hydroxy-N-heterocycles is a standard reaction in medicinal and agricultural chemistry and has heen reviewed [36]. The hitherto commonly used two-step procedure for amination of hydroxy-N-heterocycles, starts with conversion into the chloro-N-heterocycles, e.g. by treatment of the hydroxy-N-heterocycle with POCI3, PCI5, or SOCI2, followed by reaction with the amine moiety. This methodology has several drawbacks however, for example ... 

Much research has been carried out into direct amination of aromatic substrates, typified by the direct conversion of benzene to aniline using ammonia and a catalyst. Although there have been many patented routes conversions, are normally low, making them uneconomic. Modem catalysts based on rhodium and iridium, together with nickel oxide (which becomes reduced), have proved more active,and such is the research activity in this area that it is only a matter of time before such processes become widely used. 

Amination of Aromatic Hydrocarbons and Heterocyclic Analogs Thereof , WO patent 0069804, to Bayer, 2000. 

Amination of aromatic nitro compounds is a very important process in both industry and laboratory. A simple synthesis of 4-aminodiphenyl amine (4-ADPA) has been achieved by utilizing a nucleophilic aromatic substitution. 4-ADPA is a key intermediate in the rubber chemical family of antioxidants. By means of a nucleophibc attack of the anilide anion on a nitrobenzene, a o-complex is formed first, which is then converted into 4-nitrosodiphenylamine and 4-nitrodiphenylamine by intra- and intermolecular oxidation. Catalytic hydrogenation finally affords 4-ADPA. Azobenzene, which is formed as a by-product, can be hydrogenated to aniline and thus recycled into the process. Switching this new atom-economy route allows for a dramatic reduction of chemical waste (Scheme 9.9).73 The United States Environmental Protection Agency gave the Green Chemistry Award for this process in 1998.74... 

Beller and coworkers recently realized a more practical system for reductive amination of aromatic aldehydes using ammonia [79]. Their preferred conditions, which require the addition of an acidic additive, are shown in Scheme 15.10. Without extensive optimization, turnover numbers of 1700 could be... 

In a similar way it is possible to perform the amination of aromatics by indirect electrochemical reduction of hydroxylamine using a combination of the Cu /Cu and redox pairs Thus, aniline and toluidine are formed from benzene... 

In the presence of 1,3-butadiene, diamino octodienes and dodecatrienes are formed Amination of aromatic compounds has been mentioned above (Sect. 3.3.3) Sensitive substituted hydroxylamines may be reduced to the amines in oxylic acid using electro-generated titanium(III)... 

Direct amination of aromatic rings 1-25 Aminoalkylation of aromatic rings 1-32 Rearrangement of N-nitroamines 1-33 Rearrangement of N-nitrosoamines... 

Table 5.33. Yield and Isomer Distribution of Aromatic Amines Obtained by Amination of Aromatic Substrates with Aminodiazoninm Tetrachloroaluminate593...

The problems of /3-amination of aromatic unsaturated ketones and their mechanism are described in [31,47,48]. The multistage character of this process and high sensitivity both to the nature of the reaction components and to the reaction conditions should be noted. For the same reactions in the literature, different data concerning kinetics are described owing to the influence of trace contaminants in the reaction mixture [47, 48]. 

Palladium-catalyzed amination of aromatic halides, developed independently by Buchwald and Hartwig, is a useful tool for the construction of C—N bonds. Caravieilhes and coworkers reported using a microreador for aromatic amination [35]. With the use of CPC CYTOS Lab System, the reaction of p-bromotoluene with piperidine gave the desired coupling produd in quantitative yields with a residence time of 7.5 min (Scheme 4.24). 

MAP and its analogues considerably accelerate the Hartwig-Buchwald amination of aromatic and heteroaromatic halides and triflates (eq simiiai- acceleration is observed for Suzuki-... 

Amination of aromatic organometalttcs.1 The reagent reacts with aromatic... 

Although there are several electrophilic a-amination methods using azodicarbox-ylates, Chen and coworkers reported the first a-amination of aromatic ketones (140) in 2007 (Scheme 6.42) [71]. They demonstrated that 9-amino-9-deoxyepicinchona alkaloid 143 was excellent organocatalyst for the direct enantioselective a-amination of aryl ketones 140 via enamine intermediate. p-Toluenesulfonic acid was used as... 

Iron catalyzed free radical amination of aromatics or free radical carbamylation, alkylation of protonated heterocycles (see 1st edition). 

Table 2. Homolytic amination of aromatic compounds with protonated iV-chloroamines...

Amination of aromatic nitro compounds often occurs smoothly and directly also on condensation with hydroxylamine in alkaline solution, the amino group normally entering ortho or para to the nitro group. One nitro group activates naphthalene derivatives sufficiently, but in the benzene series two are necessary to induce this reaction. 2-Nitro-l-naphthylamine was thus obtained (80%) from 2-nitronaphthalene,400 and 4-nitro-l-naphthyl-amine (60%) from 1-nitronaphthylamine.401 The amino group also enters the nitrated ring of quinoline derivatives. 

Reaction of N-chloramines with aromatics [(153)-(155)] has been illustrated most recently with alkylaromatics by Clerici et al. (1974). Amination of aromatics is an electrophilic rather than free-radical... 

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