Platinum aromatic amines

INDICATIVE OXIDATION OF AROMATIC AMINES IN PLATINUM METALS CATALIMETRY... 

Aromatic amine-Ketone. The interaction between anihne, the simplest of the aromatic amines with acetone in the presence of various catalysts to yield N-isopropylaniline was examined (Table 17.3). Among the catalysts tested, sulfided platinum catalysts were found to be the most active catalysts for this reaction. 

Aromatic amines are hydrogenated in the rings by catalytic hydrogenation. Aniline yields 17% of cyclohexylamine and 23% of dicyclohexylamine over platinum dioxide in acetic acid at 25° and 125 atm [5]. A better yield (90%) of cyclohexylamine was obtained by hydrogenation over nickel at 175° and 180... 

A typical electrochemical reaction for an aromatic amine (benzidine) is shown in Figure 2. Most of the HPLC/EC work to date has been conducted using carbon working electrodes and thus the oxidative mode of the detector has been exploited (e.g. for benzidine) to the greatest extent. However, platinum and mercury have been used successfully for electroreducible species such as metal ions =/ and parathionC .). ... 

Aliphatic and Aromatic Amine Complexes 52.5.2.1 Amine complexes of platinum(II)... 

While aromatic amines in the ground state are good bases, the electron density at the amine nitrogen is drastically reduced in the first excited singlet state. On absorption of light an amine is therefore readily displaced from platinum(II). The complex dr-PtCl2( 1 -naphthylamine)2 is displaced with a quantum yield of 0.1 0.02 on irradiation at 280 or 313 nm in aqueous DMF (equation 315).947... 

Emerson and Waters alkylated primary aromatic amines with C2-C7 aliphatic aldehydes and benzaldehyde over Raney Ni in the presence of sodium acetate as a condensing agent and obtained /V-alkylanilincs in 47-65% yields.33 With C2-C5 aldehydes, up to 10% of the tertiary amines were produced, but no tertiary amines were found in the case of heptanal and benzaldehyde. With acetaldehyde in the absence of sodium acetate, aniline was recovered unchanged over platinum oxide and a mixture of amines resulted over Raney Ni, compared to 41 and 58% yields of N-ethylaniline over platinum oxide and Raney Ni (eq. 6.12), respectively, in the presence of sodium acetate. 

Aminopyridine behaves like an aromatic amine and has been hydrogenated without difficulty over platinum oxide in dilute hydrochloric acid to give 3-aminopiperidine dihydrochloride.56 4-Aminopyridine was hydrogenated only very slowly over plati-... 

Azobenzenes may be prepared by oxidation of hydrazobenzenes this may be made in an undivided cell by reduction of the nitro compound with constant current [178]. Additionally, azobenzenes may be obtained in low to fair yield by anodic oxidation of aromatic amines at a rotating platinum screen cylinder anode in aqueous DMF [179]. 

Oxidative carbonylation of aliphatic and aromatic amines in the presence of supported platinum metals or platinum metal salts as catalysts and iodide ions gives carbamates [118, 119]. Iodide is presumed to promote the partial redox reactions... 

Oxide catalysts such as cobalt oxide and nickel oxide233 are recommended for hydrogenation of primary aromatic amines to saturated primary amipes the formation of secondary and tertiary amines, and of deaminated products, is avoided by use of these catalysts. Secondary and tertiary amines can be hydrogenated with Raney nickel. Addition of concentrated hydrochloric acid during hydrogenation of primary unsaturated amines with platinum metals leads predominantly to primary amines. 

Primary aromatic amines can be reductively alkylated in satisfactory yields by aliphatic aldehydes in alcoholic solution containing a platinum or nickel catalyst at 3 atm hydrogen pressure if sodium acetate is also present.1002... 

While Wheland (91) suggests that 4-aminopyridine is an aromatic amine little success has been achieved in hydrogenation. Orthner (92) cites failure with platinum catalysts under a variety of conditions. Very low yield (16.5%) resulted from reduction of the hydrochloride salt with platinum catalyst under 80 atm pressure (93). In the reduction of A7-(4-pyridyl)morpholine where the 4-amino nitrogen atom is tertiary, hydrogenation in alcohol was successful with ruthenium (5), but unsuccessful with rhodium on alumina or platinum oxide in acetic acid. It is possible that the pressure conditions used for reduction with ruthenium catalysts may be conducive to conversion of 4-aminopyridine, since these catalysts are less inhibited by strong nitrogen bases. 

In recent years a large number of polyclonal and monoclonal antisera have been produced against adducts or modified DNA samples of a variety of chemical classes, including methylating and ethylating agents, aromatic amines, polycyclic aromatic hydrocarbons (PAH), aflatoxins, psoralens and platinum-ammine complexes (1.2). These antisera have been used to establish highly-sensitive quantitative immunoassays and have been adapted for immunohistochemistry, and electron microscopy. 

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