INDEX addition reactions

Commercial cyclohexene was used (the purity was checked by refractive index). Addition of cyclohexene caused a darkening of the reaction mixture. This is caused by a finite concentration of the osmate ester. The reaction becomes lighter in color when complete. 

Other synthetics derived from petroleum, having high viscosity index, low volatility, and low pour point, include polyoxyethylene and polyoxypropylene monohydroxy compounds (22). These can be made by an addition reaction between a monohydric alcohol and an alkylene oxide. 

Diazo transfer reactions p-Toluenesulfonyl azide, 226 Diazotization Sodium nitrite, 170, 282 Dicarboxylation (see Addition reactions to carbon-carbon multiple bonds) Diels-Alder reaction (For a list of dienes and dienophiles see Type of Compound Index)... 

An attempt has been made to analyse whether the electrophilicity index is a reliable descriptor of the kinetic behaviour. Relative experimental rates of Friedel-Crafts benzylation, acetylation, and benzoylation reactions were found to correlate well with the corresponding calculated electrophilicity values. In the case of chlorination of various substituted ethylenes and nitration of toluene and chlorobenzene, the correlation was generally poor but somewhat better in the case of the experimental and the calculated activation energies for selected Markovnikov and anti-Markovnikov addition reactions. Reaction electrophilicity, local electrophilicity, and activation hardness were used together to provide a transparent picture of reaction rates and also the orientation of aromatic electrophilic substitution reactions. Ambiguity in the definition of the electrophilicity was highlighted.15... 

Using their CNDO results Helland and Skancke calculated indices of reactivity (frontier electron density, FED, for electrophilic substitution frontier orbital density, FOD, for nucleophilic substitution frontier radical density, FRD, for radical substitution) for the thienopyridines. It was indicated that the FED index has its highest value for C-3 in the [2,3-]- and 3,2- -fused systems and for C-2 in the [3,4-1-fused isomers. As far as the former group is concerned, the predictions are in agreement with experimental observations (see Section IV,A.). Little experimental evidence is available for the [3,4-]-fused systems, but it seems highly probable that they would have a considerable tendency to undergo addition reactions at the 1,3-positions, since the product would contain a normal rather than a quinoid pyridine ring [Eq. (23)]. 

ATRP has been also utilized for the synthesis of an AB4 miktoarm star copolymer, where A is a PNIPAM block and B is a PDEAEMA block [53], At first, a mono-amino terminated PNIPAM homopolymer was synthesized. Subsequently, an addition reaction on the amino group using glycidol was realized, followed by esterification with excess 2-bromoisobutyryl bromide. The end functionalized PNIPAM formed in this way could be used as a tetrafunctional macroinitiator for the polymerization of DEAEMA monomers via ATRP. The formation of pme AB4 miktoarm star copolymer was assumed by the authors based on results from size exclusion chromatography. However, the polydispersity index was quite high (Mw/Mn= 1.23), therefore, SEC alone could not unambiguously confirm the level of purity of the miktoarm stars. 

The maleimides can be cured by an addition reaction in which no volatiles are evolved. One of the remarkable features of the polymers is their high LOI s (limiting oxygen index) of 100. In other words, these materials do not burn in the presence of oxygen, even when the samples are preheated to 300 0. 

Many years later Weber indicated that the natural rubber molecule was unsaturated since it reacted with bromine to give a material of empirical formula C5H8Br2. This clearly implied an addition reaction to a double bond. This was borne out by the more accurate and reliable iodine chloride method of Kemp in 1927 and the refractive index technique of Macallum and Whitby in 1924. 

It may be shown that My, > M (x > x ). The averages are equal only for a monodisperse polymer, where aU of the chains are exactly the same length. The ratio My,IM = Xy/x is known as the polydispersity index, PI. PI is a measure of the breadth of the molecular weight distribution. A monodisperse sample would have a PI of 1.0, but typical values range from about 1.02 for carefully fractionated polymers synthesized by anionic addition reactions to over 50 for some commercial polymers. 

Additives for lubricating oils providing a combination of viscosity index improvement (VII) and dispersancy have also been reported. These additives are prepared from ethyleneamines by reaction with various Vll-type polymers that have been chlorinated or modified in some other way to provide an ethyleneamine reaction site. Antimst additives for lubricating oils have been prepared by reaction of polyamines with fatty acids followed by reaction with polyalkylenesuccinic anhydrides (178,179). 

Ethyl Vinyl Ether. The addition of ethanol to acetylene gives ethyl vinyl ether [104-92-2] (351—355). The vapor-phase reaction is generally mn at 1.38—2.07 MPa (13.6—20.4 atm) and temperatures of 160—180°C with alkaline catalysts such as potassium hydroxide and potassium ethoxide. High molecular weight polymers of ethyl vinyl ether are used for pressure-sensitive adhesives, viscosity-index improvers, coatings and films lower molecular weight polymers are plasticizers and resin modifiers. 

This index contains over 25 000 entries to the 6562 text pages of Volumes 1-6. The index covers general types of coordination complex, specific coordination complexes, general and specific organic compounds where their synthesis or use involves coordination complexes, types of reaction (insertion, oxidative addition, etc.), spectroscopic techniques (NMR, IR, etc.), and other topics involving coordination complexes, such as medicinal and industrial applications. 

Yield and other mass-related metrics such as atom economy, reaction mass efficiency and mass intensity have been examined by Constable et al with regard to their significance concerning greenness and costs. The importance of using a (product) concentration term, which can be mass intensity or mass index, is additionally emphasized by Laird et al This is in compliance with Winterton, who in his twelve more green chemistry principles demands the establishment of full mass balances. 

The qualitative voltammetric behavior of methanol oxidation on Pt is very similar to that of formic acid. The voltammetry for the oxidation of methanol on Pt single crystals shows a clear hysteresis between the positive- and negative-going scans due to the accumulation of the poisoning intermediate at low potentials and its oxidation above 0.7 V (vs. RHE) [Lamy et al., 1982]. Additionally, the reaction is also very sensitive to the surface stmcture. The order in the activity of the different low index planes of Pt follows the same order than that observed for formic acid. Thus, the Pt(l 11) electrode has the lowest catalytic activity and the smallest hysteresis, indicating that both paths of the reaction are slow, whereas the Pt( 100) electrode displays a much higher catalytic activity and a fast poisoning reaction. As before, the activity of the Pt(l 10) electrode depends on the pretreatment of the surface (Fig. 6.17). 

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