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Amines quinones

Some bridgehead amines [l,4-diazabicyclo-[2,2,2]octane (102), quinuclidine (103) and quinuclidine-3-ol] form 1 1 molecular complexes with quinones 104. Formation of 2 1 (amine/quinone) complexes was observed in solutions of DABCO (102) and chloranil (104, R = Cl). These tertiary amines are able to form complexes, while non-bridgehead amines (triethylamine, piperidine) cannot because of steric hindrance or nitrogen inversion183. Stable complexes may be predicted (by CNDO/2 calculations) for... [Pg.401]

Fig. 3.8. (a) A Structure of the hydroquinone-containing poly(siloxane). B Structure of the hydroquinone-containing poly(acrylonitrile-ethylene). The m n ratio is approximately 1 2 for both systems. Reprinted with permission from [10]. (b) Structure of the polyCether amine quinone) polymers. Reprinted with permission from [15], 1994 American Chemicad Society. [Pg.357]

FIGURE 11.3. (a) Structure of poly(ether amine quinone). (b) Cyclic voltammogram for the cross-linked poly(ether amine quinone)/glucose oxidase/carbon paste electrode in phosphate buffer of pH 7.0 scan rate 5 mV/s, added electrolyte 0.1 M KCl (I) glucose absent and (II) 0.1-M glucose present. (From Ref. 53). [Pg.306]

Pollutants treated in synthetic solutions include phenols, aromatic amines, quinones, glucose, carboxylic acids, tannic acid, herbicides, pesticides, surfactants, dyes, etc. [2-5]. Some papers have considered the treatment of real effluents including human wastes, landfill leachates, tannery wastes, dye plant effluents, and herbicide manufacture effluents [4—7]. [Pg.578]

Pofy(ether amine quinone)s as Electron-Transfer Relay Systems in Amperometric Glucose Sensors... [Pg.124]

Antirad compounds decrease the rate of reactions including both crosslinking and chain scission. As a result they often provide protection against polymer degradation. Antirads include aromatic amines, quinones, aromatic sulfur and nitrogen compounds. These materials are highly... [Pg.162]

Reactions with Organic Compounds. Tetrafluoroethylene and OF2 react spontaneously to form C2F and COF2. Ethylene and OF2 may react explosively, but under controlled conditions monofluoroethane and 1,2-difluoroethane can be recovered (33). Benzene is oxidized to quinone and hydroquinone by OF2. Methanol and ethanol are oxidized at room temperature (4). Organic amines are extensively degraded by OF2 at room temperature, but primary aHphatic amines in a fluorocarbon solvent at —42°C are smoothly oxidized to the corresponding nitroso compounds (34). [Pg.220]

Oxidation of LLDPE starts at temperatures above 150°C. This reaction produces hydroxyl and carboxyl groups in polymer molecules as well as low molecular weight compounds such as water, aldehydes, ketones, and alcohols. Oxidation reactions can occur during LLDPE pelletization and processing to protect molten resins from oxygen attack during these operations, antioxidants (radical inhibitors) must be used. These antioxidants (qv) are added to LLDPE resins in concentrations of 0.1—0.5 wt %, and maybe naphthyl amines or phenylenediamines, substituted phenols, quinones, and alkyl phosphites (4), although inhibitors based on hindered phenols are preferred. [Pg.395]

Rifamycin S also undergoes conjugate addition reactions to the quinone ring by a variety of nucleophiles including ammonia, primary and secondary amines, mercaptans, carbanions, and enamines giving the C-3 substituted derivatives (38) of rifamycin SV (117,120,121). Many of the derivatives show excellent antibacterial properties (109,118,122,123). The 3-cycHc amino derivatives of rifamycin SV also inhibit the polymerase of RNA tumor vimses (123,124). [Pg.498]

The kinetics of formation and hydrolysis of /-C H OCl have been investigated (262). The chemistry of alkyl hypochlorites, /-C H OCl in particular, has been extensively explored (247). /-Butyl hypochlorite reacts with a variety of olefins via a photoinduced radical chain process to give good yields of aUyflc chlorides (263). Steroid alcohols can be oxidized and chlorinated with /-C H OCl to give good yields of ketosteroids and chlorosteroids (264) (see Steroids). /-Butyl hypochlorite is a more satisfactory reagent than HOCl for /V-chlorination of amines (265). Sulfides are oxidized in excellent yields to sulfoxides without concomitant formation of sulfones (266). 2-Amino-1, 4-quinones are rapidly chlorinated at room temperature chlorination occurs specifically at the position adjacent to the amino group (267). Anhydropenicillin is converted almost quantitatively to its 6-methoxy derivative by /-C H OCl in methanol (268). Reaction of unsaturated hydroperoxides with /-C H OCl provides monocyclic and bicycHc chloroalkyl 1,2-dioxolanes. [Pg.475]

Under the influence of peroxides aromatic amines (color developer 3) react with phenols to yield quinone imines [1]. [Pg.369]

Aromatic amine + 1-Naphthol-----------------> Quinone imine dyestuff. [Pg.369]

Dioxo-2, 4, 5 -trimethylcyclohexa-l, 4 -diene)-3,3-dimetbylpropi-onamide (Q). The application of this well-known acid [3-(3, 6 -dioxo-2, 4, 5 -trimethylcyclohexa-l, 4 -diene)-3,3-dimethylpropionic acid] to protection of the amino function for peptide synthesis has been examined. Reduction of the quinone with sodium dithionite causes rapid trimethyl lock -facilitated ring closure with release of the amine. [Pg.562]

The reduction of benzofuroxans can lead to a variety of products, depending upon the conditions. Deoxygenation to benzofurazans (40) can be effected either directly, using trialkyl phosphites, -tributyl or triphenyl - phosphine, or indirectly, via o-quinone dioximes (41), using methanol and potassium hydroxide, or hydroxyl-amine and alkali. - - The dioximes may be isolated, but... [Pg.21]

B. Naphthaquinone method Discussion. Many primary amines develop a blue colour when treated with ortho-quinones the preferred reagent is the sodium salt of l,2-naphthaquinone-4-sulphonic acid. [Pg.705]

Photoredox systems involving carbonyl compounds and amines are used in many applications. Carbonyl compounds employed include benzophenone and derivatives, a-diketones [e.g. benzil, cainphoroquinone (85),2W 291 9,10-phenanthrene quinone], and xanthone and coumarin derivatives. The amines are tertiary and must have a-hydrogens [e.g. N,A7-dimethylani 1 ine, Michler s ketone (86)]. The radicals formed are an a-aminoalkyl radical and a ketyl radical. [Pg.102]

The major problem of these diazotizations is oxidation of the initial aminophenols by nitrous acid to the corresponding quinones. Easily oxidized amines, in particular aminonaphthols, are therefore commonly diazotized in a weakly acidic medium (pH 3, so-called neutral diazotization) or in the presence of zinc or copper salts. This process, which is due to Sandmeyer, is important in the manufacture of diazo components for metal complex dyes, in particular those derived from l-amino-2-naphthol-4-sulfonic acid. Kozlov and Volodarskii (1969) measured the rates of diazotization of l-amino-2-naphthol-4-sulfonic acid in the presence of one equivalent of 13 different sulfates, chlorides, and nitrates of di- and trivalent metal ions (Cu2+, Sn2+, Zn2+, Mg2+, Fe2 +, Fe3+, Al3+, etc.). The rates are first-order with respect to the added salts. The highest rate is that in the presence of Cu2+. The anions also have a catalytic effect (CuCl2 > Cu(N03)2 > CuS04). The mechanistic basis of this metal ion catalysis is not yet clear. [Pg.27]

On the other hand, there is at least one case of an aromatic amine without a hydroxy group in the 2-position, namely 1-aminophenazine (2.29) which, after the initial diazotization, is oxidized within minutes by air or additional nitrous acid to the quinone diazide 2.31 (Olson, 1977). [Pg.27]

Compounds which correspond to 1,2-quinone diazides can also be obtained by diazotization of aromatic and nonaromatic heterocyclic amines with a hydroxy group in the ortho position. Examples include 3,4-quinolinequinone-3-diazide (2.35, Sus et al., 1953 Sus and Moller, 1955) and 3-diazochromane-2,4-dione (2.36, Arndt et al., 1951). Syntheses of more complex heterocyclic quinone diazides have been tabulated by Ershov et al. (1981, p. 105). More recent publications are cited in a paper by Tisler s group (Klotzer et al., 1984). [Pg.29]


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See also in sourсe #XX -- [ Pg.36 , Pg.39 ]




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Amination quinones

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