Composition of reaction mixtures

Table 13 The composition of Reaction Mixture Used to Make Lignin Graft Copolymers...

Table VII. The Composition of Reaction Mixtures Used Lignin Graft Copolymers to Make...

Scheme 36. Composition of reaction mixtures in the ECF of 4-(perfluoro-n-butyl)-n-butanoyl chloride (Expts.l -4) and n-octanoyl chloride (Expts.5-6)...

Composition of reaction mixture same as in Table I. b Calculated from x-ray analysis. c Calculated from N2 sorption. 

A thorough investigation of the composition of reaction mixtures has revealed (86MI2) that the KOH/DMSO-catalyzed synthesis of pyrroles from ketoximes and acetylene is accompanied by the formation of Z-l-(2-methylthiovinyl)pyrroles (99), which can be isolated in a yield of about 0.1% (Scheme 48). The pyrroles 99a-c are characterized in detail (86MI3) by H-NMR (Table XXV). I3C-NMR, IR and mass spectra. 

The first free radical initiated copolymerization was described by Brubakerl) in a patent. A variety of peroxides and hydroperoxides, as well as, 02, were used as initiators. Olefins that were copolymerized with CO included ethylene, propylene, butadiene, CH2=CHX (X—Cl, OAc, CN) and tetrafluoroethylene. A similar procedure was also used to form terpolymers which incorporated CO, C2H4 and a second olefin such as propylene, isobutylene, butadiene, vinyl acetate, tetrafluoroethylene and diethyl maleate. In a subsequent paper, Brubaker 2), Coffman and Hoehn described in detail their procedure for the free radical initiated copolymerization of CO and C2H4. Di(tert-butyl)peroxide was the typical initiator. Combined gas pressures of up to 103 MPa (= 15,000 psi) and reaction temperatures of 120—165 °C were employed. Copolymers of molecular weight up to 8000 were obtained. The percentage of CO present in the C2H4—CO copolymer was dependent on several factors which included reaction temperature, pressure and composition of reaction mixture. Close to 50 mol % incorporation of CO in the copolymer may be achieved by using a monomer mixture that is >70 mol% CO. Other related procedures for the free radical... 

Figure 3.1 The composition of reaction mixture as a function of reaction time in the hydrogenation of 1,5-cyclooctadiene over unpoisoned (a), phenylacetaldehyde-poisoned (b), and carbon monoxide-poisoned (c) palladium catalysts. The points are experimental values, and the curves show the simulations using the values given in Table 3.4. For the reaction conditions, see footnote b in Table 3.4. (Key 1,5-COD 1,4-COD O COE 9 COA. (For abbreviations, see Scheme 3.9.) (FromHigashijima, M. Ho, S.-M. Nishimura, S. Bull. Chem. Soc. Jpn. 1992, 65, 2960. Reproduced with permission of Chemical Society of Japan.)...

The composition of reaction mixtures obtained under classical Fischer-Zach conditions was determined by capillary gas chromatography [53] of per-O-silylated and per-O-acetylated components of the crude reaction mixtures, and some progress was made in explaining the mechanism behind typical side-product formation. The compounds identified included products of solvolytic displacement of an anomeric bromine by acetic acid and water as well as 2,3-unsaturated derivatives. Interestingly, there was a difference in the reaction outcome of pentopyranosyl versus hexopyranosyl substrates. In the former case, glycals were accompanied by acetylated 1,5-anhydropentitols in the latter, hex-l-enitols contained admixtures of peracetylated 2-deoxyhexopyranosides. 

The composition of reaction mixture can be controlled by additives including Zn-, Sn- and P-compounds... 

With higher olefins the product distribution becomes more variable. Not only the expected enol acetates but also allylic acetates are formed. Thus, propene forms isopropenyl acetate along with some n-propenyl acetate and allyl acetate [6, 7]. Higher and cyclic olefins react to form mainly allylic esters [8-18] moreover pre-isomerization of the olefins give rise to an even broader spectrum of products. The results published differ from each other, probably because of different reaction conditions and composition of reaction mixtures. 

Most of the studies dealing with the effect of the composition of reaction mixture on the catalytic hydrogenation in the liquid state have been devoted to olefinic substrates. The reactions proceed at readily measurable rates already under normal conditions, so that their experimental investigation is not technically demanding. The system enables the structure of compounds undergoing hydrogenation to be varied within broad limits it also makes possible the use of a broad variety of solvents, and is very suitable for the given purpose. 

Fig. 4-5 Composition of reaction mixture vs conversion for the sulfurization of methane...

Fig.4 is the experimental results for combustion temperature profiles of some kinds of compositions according to Tc = 2000K and corresponding design of compositions of reaction mixtures. 

Under the reaction conditions used for the kinetic measurements, no formation of intermediates (e.g. nitroso, hydroxylamino or hydrazo compounds) could be observed. The composition of reaction mixtures was checked by thin layer and gas chromatography, monitored by UV-Vis spectroscopy and finally verified by GUMS, H- and 3Q.j,jMR-spectroscopy. 

Experimental determinations of the composition of reaction mixtures at equilibrium leads to the concept of the position of equilibrium, and to a further general principle about chemical equilibria the meaning and formulation of the equilibrium constant. This is one of the most important principles in the whole of chemistry and governs many aspects of the behaviour of electrolyte solutions. 

Chemical kinetics is the study of the rates of chemical reactions. Such reaction rates range from the almost instantaneous, as in an explosion, to the almost unnoticeably slow, as in corrosion. The aim of chemical kinetics is to make predictions about the composition of reaction mixtures as a function of time, to understand the processes that occur during a reaction, and to identify what controls its rate. 

We have investigated the effect of various parameters such as catalyst concentration, [PS-Br]/[F-R-Br] ratio, PS-Br concentration, and time dependence on the ATRCC system. It has also been observed that under these experimental conditions the highest functionalization is achieved after 2h and then the composition of reaction mixture does not change significantly with timo (Figure 3). 

Figure 3. Photochemical action spectrum of reconstituted llp-hydroxylase system. Curve is a composite of five experiments, three in the range 450-401 mfx and two in the range 450-500 mfx. Experimental procedure and composition of reaction mixture are described in Table 11 concentrations of Fp and NHI given in Flask 6 of Table II. Rate of corticosterone formation in the absence of CO averaged 9 nmole/mg. P-3 protein/min. Flasks were gassed with 4% O2-96% Ngor4% Og-4.2% CO-91.8% N/CO/O2 ratio = 1.05). The ordinate scale is relative light sensitivity Lx/L 50. L is calculated as described in Table III. The wavelength of monochromatic light of approximately equal intensity illuminating the reaction vessels is plotted on the abscissa...

Approximate composition of reaction mixture 30 mL trimethylchlorosilane + 20 mL THF + 10 mmol hydrate. 

The Equilibrium Constant. Experimental results concerning equilibrium compositions of reaction mixtures are conveniently summarized by presenting tables of equilibrium constants. The equilibrium constant of a reaction K is defined by the relation... 

Fig. 9.2 Composition of reaction mixture as a function of time in the cross-metathesis of a 1 1 mixture of cw-pent-2-ene with 4-methylpent-l-ene. Catalyst Bu4N[MoCl(CO)5]/...

Figure 11.3. Variation of composition of reaction mixture with time for a conventional Wurtz synthesis in boiling toluene (Reprinted with permission from ref Copyright 2000 Kluwer Academic Publishers).

Corey showed 1963 that 2-exo-103 and 2-endo-norbornylamines 104 are deaminat-ed in acetic acid to yield practically identical mixtures both in the exo endo product ratio and in the retention degree of optical activity. He postulated both reactions to the same intermediate classical 2-norbornyl cation since no optically active products were obtained from a symmetrical nonclassical 2-norbornyl ion 5. Somewhat later Berson studied the composition of reaction mixtures from the deamination of amines 103 and 104 (Table 8) more carefully three essential difference in the compositions of reaction mixtures were pointed out ... 

Fig. 23. Composition of reaction mixture during hydrogenation of allyl alcohol in the presence of Pd black (a) and P4VP-Pd(0) (b) in water at 293 K. 1 - allyl alcohol 2 - propanol 3 -propionic aldehyde [71]...

Table 7.2 Sample results for composition of reaction mixture during s)mthesis of ammonia (7.4.27) based on an initial loading of 3 moles of H2 plus 1 mole of N2...

From kinetic reason the composition of reacting mixtures is frequently very complicated and far from eqmhbrium. It should be reminded that the thermodynamic permits to determine the equilibriiun phase composition of reaction mixture this state has the lowest free enthalpy. This principle permits to find a priori the direction of reaction course or permits to determine the phases stability in determined thermodynamie conditions. The change of free enthalpy can be found from the Gibbs-Helmholtz s equation [13] ... 

Fig. 6 Volta-potential as a ftmction of pH of an aqueous solution. Composition of reaction mixture 20 mM tris-HCl + 1 mM NADH + 10 M 2-JV-methylamino-l,4-naphtoquinone + 5 g/ml chlorophyll [48]...

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