Non-oxidative conditions

For example,copper has relatively good corrosion resistance under non-oxidizing conditions. It can be alloyed with zinc to yield a stronger material (brass), but with lowered corrosion resistance. Flowever, by alloying copper with a passivating metal such as nickel, both mechanical and corrosion properties are improved. Another important alloy is steel, which is an alloy between iron (>50%) and other alloying elements such as carbon. 

The reaction of ozone with an aromatic compound is considerably slower than the reaction with an alkene. Complete ozonolysis of one mole of benzene with workup under non-oxidative conditions will yield three moles of glyoxal. The selective ozonolysis of particular bonds in appropriate aromatic compounds is used in organic synthesis, for example in the synthesis of a substituted biphenyl 8 from phenanthrene 7 ... 

Acyl nitroso compounds react with 1, 3-dienes as N-O heterodienophiles to produce cycloadducts, which have found use in the total synthesis of a number of nitrogen-containing natural products [21]. The cycloadducts of acyl nitroso compounds and 9,10-dimethylanthracene (4, Scheme 7.3) undergo thermal decomposition through retro-Diels-Alder reactions to produce acyl nitroso compounds under non-oxidative conditions and at relatively mild temperatures (40-100°C) [11-14]. Decomposition of these compounds provides a particularly clean method for the formation of acyl nitroso compounds. Photolysis or thermolysis of 3, 5-diphenyl-l, 2, 4-oxadiazole-4-oxide (5) generates the aromatic acyl nitroso compound (6) and ben-zonitrile (Scheme 7.3) [22, 23]. Other reactions that generate acyl nitroso compounds include the treatment of 5 with a nitrile oxide [24], the addition of N-methyl morpholine N-oxide to nitrile oxides and the decomposition of N, O-diacylated or alkylated N-hydroxyarylsulfonamides [25-29]. 

A. Catalytic Transformation of Methane into Aromatics Under Non-OxiDATiVE Conditions... 

Mass related distribution coefficients for Tc and U under non-oxidizing conditions (25 C, Aquog)... 

Retention in the Hostrock. For granite, apparent surface to mass ratios of about 3 m /kg for Cs, 2 m /kg for divalent elements and <10 m /kg for tri- and tetravalent elements have been estimated, based on Kd/Ka-measurements on Cs, Sr and Am on granitic macro surfaces (1,31). Retention factors are given in Table IX, as generated from measured K.-values (from Table V), assuming long contact time, non-oxidizing conditions and representative fracture and permeability data for the rock (p. 

Proposed retention factors (Kj) in granite (25 C, long contact time, non-oxidizing conditions)... 

Heterogeneous catalysts activate C—H bonds at significantly higher temperatures. For example, a Fe/Co modified Mo-supported acidic ZSM-5 zeolite catalyst dehydrogenates methane under non-oxidizing conditions at 700°C to a mixture of Q-C4 alkanes/alkenes and Q-Q2 aromatics such as benzene and naphthalene.140... 

The good activity and the almost 100% selectivity to aromatics (mainly is benzene and toluene) have been obtained for the conversion of CH4 to aromatics over Mo(Vl) /HZSM-5 catalysts as reported previously [2-3]. CH4 activation under non-oxidizing conditions over bifunctional Mo(Vl)/HZSM-5 is initiated by CH3+ carbonium ion formation and the CH3+ further forms CH2 carbene active transients as proposed in [2, 3], The reaction mechanism suggested is as follows ... 

The photocyclisation of A-phenyl-3-vinylquinolin-2( )-ones provides a facile route to benzo[k]phenanthridones. Under non-oxidative conditions, the tetrahydro derivative results, but photolysis in the presence of iodine gives the fully aromatic heterocycle. Introduction of a 2-chlorine substituent into the starting material results in the formation of 6-chloro-7,8-dihydrobenzophen-anthridones (K. Veeramani et al.. Synthesis, 1978, 855). 

The initial photochemical step, (211) to (212), can be most simply viewed as a perturbed 6e electrocy-clic process, suggesting a trans configuration via conrotation for die dihydrophenanthrene intermediate (212). In support of this hypothesis, the stabilization of (216) by tautomerism to (217) in the photolysis of diethylstilbestrol (214), followed by ozonolysis, aiffor d only the racemic form of 1,2,3,4-buta-netetracarboxylic acid (218).The majority of dihydrophenanthrenes, however, are thermally unstable and undergo conversion to phenanthrenes (under oxidative or non-oxidative conditions) or l -H shifts to isomeric 9,10-dihydrophenanthrenes. ... 

The effect of several metal substrates have been examined on the photodegradation rate of poly(ethyleneterephthalate). Relative stabilities were in the order Cu > A1 > control polymer > Au > Ag under non-oxidative conditions. Under oxidative conditions only the Cu proved to be a photosensitiser499. No mechanistic explanations were apparent. The effect of new catalyst systems have been examined on the rate of photodegradation of polyester fibres OO, Apparently, whilst the use of Ti, Ge and A1 glycolate catalysts gave lower molecular weight products they proved to be more light stable than those prepared with antimony. Dye stability was also markedly improved. 

The reaction of a nucleophilic alkyl radical R with benzene affords the a-complex 1, a fairly stable cyclohexadienyl radical, which under oxidizing conditions leads to cation 2 (Scheme 1). Depending on the stability of the attacking radical, the formation of 1 is a reversible process. Deprotonation eventually affords the homolytic aromatic substitution product 3. If the reaction is performed under non-oxidizing conditions, cyclohexadienyl radical 1 can dimerize (—> 4), disproportionate to form cyclohexadiene 5 and the arene 3, or further react by other pathways [3]. 

The above survey of the literature has largely dealt with the analysis of the changes in molecular structure in polymers irradiated in the absence of air. The vast majority of the literature has been concerned with irradiation in non-oxidative conditions due to the desire to identify the fundamental processes occurring on radiolysis. However, the influence of oxygen on the radiation chemistry of polymers is profound and must not be ignored. To this end a number of papers have been concerned with the measurement of changes in the NMR spectra of polymers irradiated in oxygen. ... 

Furane resins are produced by self-condensation of fiirfuryl alcohol with furfural. They offer possibly the best chemical resistance of any thermosetting resin in non-oxidizing conditions, and have excellent resistance to solvents. Flowever, they also require acidic catalysts that give a complication in processing. 

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