Reaction temperature dependency

The thus formed heterocycles 412a decompose or isomerize thermally the required reaction temperature depends on the substituents. The isomerization leads to diazomethane derivatives 413a, whereas the decomposition by [2 + 3] cycloreversion reaction gives bis(trimethylsilyl)diazomethane and short-lived silanimines 414a, which dimerize in most cases. The ratio isomerization/cycloreversion depends on R, the solvent and the temperature and more cycloreversion is observed at higher temperature. An unfavourable side reaction is the insertion of Me2Si=NR into Si—N bonds (formation of 415a and 686 see below). 

Equilibrium Implied Formation Reaction Temperature Dependent Parameters ... 

Reaction temperature depends on the flowrates and concentrations but they are consistently between 580°C and 650°C. 

Reaction teffperature. Tlie inlluencc of che reaction temperature depends on the catalysts used. With nonpromoted cobalt catalysts, the best... 

Table 1 - Summary of HO2 + HO2 reaction temperature dependence studies at low pressure.

The reaction is performed at a temperature between approximately -20° C. and the boiling point of the corresponding solvent. The reaction times are dependent on the catalyst, the solvent, the water binding substance and the reaction temperature. Dependent on the selected conditions times from a few minutes to several days are required. 

Direct combination of the elements (about minimum reaction temperatures, depending on the starting materials see Section 3.6.1). 

Preocanin, T., Krehula, S.. and Kallay, N., Enthalpy of surface reactions Temperature dependency of pH of acidic or basic concentrated hematite suspension, Appl. Surf. Sci., 196, 392, 2002. 

The choice of reaction temperature depends on several aspects. High temperatures favor the activity of the catalyst system and increase the partial pressure of n-1-butene (b.p. — 6.1 °C) but have a negative impact on the long-term ligand stability. As a compromise a reaction temperature 5-10°C higher than in the hydroformylation of propene is acceptable. Also, with respect to the partial pressure of n-l-butene the overall pressure is lower about 40 bar has been proven suitable. The stripping column, as the central unit in the process, deserves special attention in order to remove dissolved butenes and butane completely from the oxo crude a balance between temperature and pressure conditions has to be established. The... 

The reaction temperature depends on the metal chloride involved. The minimum temperature is that necessary (see Reference 2) to melt or volatilize the trichloride which coats the metal and thereby inhibits reaction. A better rate of reaction will be achieved 50-150° higher, under which conditions the halide sublimes as well as melts and overflows the crucible. The conversion takes 0.5-4 hr depending on quantities and temperatures. 

Figure 13 Reaction temperature dependences of methanol selectivity and conversion on Cu-Zr02 (O, ) and Cu-ZnO ( , ) catalysts prepared from nitrates (NNN-1 and NNN-9 In Table 4, respectively) (from Reference 25, reprinted with permission).

Fig. 4 Reaction temperature dependence of the glycerol hydrogenolysis over Rh-ReOjySi02 (Re/Rh = 0.5) [33] (a) and Rh/Si02 (b). Reaction conditions Glycerol 4 g, water 16 g. West = 0.15 g, P(H2) = 8 MPa, / = 2 h (Rh-ReO /Si02) or 10 h (Rh/Si02). PrD propanediol, PrOH propanol. Degradation ethylene glycol + ethanol + methanol + methane. Reprinted with permission from Elsevier [33]...

FIGURE 3.5 The H + H2 H2 + H reaction. Temperature dependence of the rate constant. 

In a seminal communication, Chiusoh et al. reported an example of an intercepted Mizoroki-Heck reaction for the first time [86]. A palladiumreducing agent, ammonium formate, produced a mixture of 146 and 147 in a reaction temperature-dependent ratio (Scheme 7.34). The minor product 147 was formed by standard intermolecular Mizoroki-Heck alkenylation and subsequent reductive cleavage of the intermediate C(sp )—Pd" bond formation of the major product 146 involved an additional intramolecular alkene insertion prior to the reduction step. 

The ammonia synthesis reaction temperature depends on the active temperature of catalyst hence the process operator should know the active temperature of catalyst. Tables 8.3 and 8.4, and Fig. 8.4 show the relationships between the activity and temperature of ZA-5, A301, ICI74-1 and AllO-2 catalysts. 

Rondot, C., Zhu, J. (2005). Synthesis of chiral vicinal diamines by highly diastereose-lective three-component phenolic Mannich reaction temperature-dependent stereodivergency. Organic Letters, 7, 1641-1644. 

Ranschaert, D.L., Schneider, N.J., Elrod, M.J. Kinetics of the C2H5O2-1-NOX reactions Temperature dependence of the overall rate constant and the C2H5ONO2 branching channel of C2H5O2-1-NO. J. Phys. Chem. A 104, 5758-5765 (2000)... 

Ternary alkali rare earth polyphosphates are also obtained in the reaction between MPO3 (M = Li, Na, K, Rb, Cs, Ag, Tl) and RPjO,. The reaction temperature depends on the alkali metal (Ferid et al., 1981 Rzaigui and Ariguip,... 

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