Differing reagent

Biphenyl is a compound which raises problems as regards the orientation of nitration produced by different reagents. This compound is discussed later ( 10.1). 

Different reagents react with different bonds in the same molecule. PCC represents pyridinium chlorochromate. 

Lithio compounds react with many different reagents, forming a variety of products (see Section 4.02.3.10). 

Many different reagents are available that allow the addition of fluorine to a double bond as exemplified in equation 1 for the addition to cw-stibene [1, 2 3 4]... 

The carbonium ion rearrangements that can be observed in halofluonnations are illustrated by the reactions ot norbornene (Table 2) and norbornadiene (Table 3). Product ratios may vary with the different reagent combinations... 

It may be unsafe to carry this discussion further until more data are available. Knowledge of the activation parameters would be especially desirable in several respects. Reactivity orders involving different reagents or substrates may be markedly dependent on temperature. Thus, in Table IV both 2- and 4-chloroquinolines appear to be about equally reactive toward sodium methoxide at 86,5°. However, the activation energies differ by 3 kcal/mole (see Section VII), and the relative rates are reversed below and above that temperature. Clearly, such relative rates affect the rs-/ ro- ratios. 

Many commercial products are derived from ethylene oxide by reacting with different reagents. The following reviews the production and the utility of these chemicals. 

The preparations of chlorins described so far by attack of different reagents at a peripheral C — C double bond of the porphyrin macrocycle are all restricted to highly symmetric porphyrins because otherwise complex mixtures of constitutional isomers can be formed. The problem of... 

The lithiation of 2-F- and 3-F-pyridines has been investigated with different reagents and reaction conditions. 

Quantitative information about the equilibrium between olefin and Br2 on the one hand and CTC s and bromonium ion species on the other (Scheme 4) has been obtained by the already mentioned UV-Vis spectrophotometric study of the adamantylideneadamantane Br2 system (ref. 10). The spectrophotometric UV-Vis data of a large set of solutions of different reagents concentrations have been used to dissect, using a program based on NLLSQ fitting procedures, the complex spectra in those of the single species present at the equilibrium, as shown in Figure 5. 

To summarize, the amounts of different reagents that participate in a chemical reaction are related through the stoichiometric coefficients in the balanced chemical equation. To convert from moles of one reagent to moles of any other reagent, multiply by the stoichiometric ratio that leads to proper cancellation of units ... 

Applications Desorption chemical ionisation has proven potential in the analysis of thermally labile, nonvolatile and polar compounds [40,67,68], for the identification of unknown polymers and the study of the thermal degradation mechanisms of polymers. Considering the overall ease of DCI operation, the capability of analysing nonvolatile compounds, and the selectivity provided by choosing different reagent gases, DCI has found surprisingly few practitioners in the analysis of polymer additives. 

For the purpose of comparing the reactivity towards different reagents, however, it may be more or less recommended to take into account the effect of the reagent orbital. In that case we need to go back to Eqs. (3.22) and (3.24). Such a type of modification of superdelocalizability has also been made 50,56,87),... 

Figure 3.7. The concept of chemistry in iutcrphascs visualisation of two different ways to obtain such a material, sol-gel procedure using different reagents (left) and silica grafted materials with sufficiently long spacers (right). Solvent occupies the space between the spacers...

In 1965, Rauhut et al. [73] reviewed the oxalyl chloride CL system and showed that oxalyl esters could be used for this system instead of oxalyl chloride. Since then, they synthesized a number of oxalates including oxamides and established a new, potent luminescent system, namely the peroxyoxalate CL (PO CL) system. Much work has been carried out to synthesize suitable oxalic compounds. The first study dealing with different reagents was published in 1967 by Rauhut et al. [98] for the American Cyanamid Company with the purpose of developing... 

Recently, Orosz et al. [136] reviewed and critically reevaluated some of the known mechanistic studies. Detailed mathematical expressions for rate constants were presented, and these are used to derive relationships, which can then be used as guidelines in the optimization procedure of the POCL response. A model based on the time-window concept, which assumes that only a fraction of the exponential light emission curve is captured and integrated by the detector, was presented. Existing data were used to simulate the detector response for different reagent concentrations and flow rates. 

Using different reagents or under various conditions, 2,3-epoxy alcohols can undergo ring-opening reactions with metallic hydrides, giving 1,3-diols or 1,2-diols. As shown in Scheme 4-16, reduction of 3-substituted 2,3-epoxy alcohols with Red-Al leads to the exclusive formation of 1,3-diols, and this can be applied in the preparation of 1,3-diol compounds.31... 

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