Reaction expander

The control of leakage loss across die blades in a reaction expander is extremely important. Maintaining adequate clearance implies preventing mechanical rubs while at die same time minimizing die loss effect on expander efficiency. 

Mannich Reactions Expanding the concept of enamine catalysis outside... 

The Lewis acid catalyzed reactions expand the scope of aldehyde substrates with certain boronate reagents. For example, whereas cyclohexanecarboxalde-hyde is unreactive nnder thermal (nncatalyzed) conditions, it does react with allylic boronate 8 nnder Sc(OTf)3 catalysis at room temperature (Eq. 53, see also Eq. 6).26... 

Such electrochemical processes can be described on the basis of the model developed by Lovric and Scholz [115, 116] and Oldham [117] for the redox reactivity of nonconducting solids able to be permeated by cations or anions (so-called ion-insertion solids). As described in the most recent version of Schroder et al. [118], the electrochemical process is initiated at the three-phase junction between the electrode, the electrolyte solution, and the solid particle, as schematized in Fig. 2.6. From this point, the reaction expands via charge diffusion across the solid particle. It is assumed that, for a reduction process, there is a flux of electrons through the... 

Chemical Reaction Mechanisms and Kinetics. CVD chemistry is complex, involving both gas-phase and surface reactions. The role of gas-phase reactions expands with increasing temperature and partial pressure of the reactants. At high reactant concentrations, gas-phase reactions may eventually lead to gas-phase nucleation that is detrimental to thin-film growth. The initial steps of gas-phase nucleation are not understood for CVD systems, not even for the nucleation of Si from silane, which has a potential application in bulk Si production (97). In addition to producing film precursors, gas-phase reactions can have adverse effects by forming species that are potential impurity sources. 

Instead of starting with racemic starting material it is also possible to use symmetric substrates [25]. The hydrolase selectively catalyses the hydrolysis of just one of the two esters, amides or nitriles, generating an enantiopure product in 100% yield (Scheme 6.7). No recycling is necessary, nor need catalysts be combined, as in the dynamic kinetic resolutions, and no follow-up steps are required, as in the kinetic resolutions plus inversion sequences. Consequently this approach is popular in organic synthesis. Moreover, symmetric diols, diamines and (activated) diacids can be converted selectively into chiral mono-esters and mono-amides if the reaction is performed in dry organic solvents. This application of the reversed hydrolysis reaction expands the scope of this approach even further [22, 24, 27]. 

A few years later, Bar-Eli and Klein (i), studying the same reaction, expanded the range of concentrations of potassium amide to 200 X lO M. Using the same dissociation constant as Wilmarth and Dayton and assuming also that the activity coefficients are equal to unity, they concluded that two catalytic species are present the free amide ion NH2 and the ion pair K NH2. ... 

KINETICS OF RAPID ELECTRODE REACTIONS Expanding (12) and (13) and equating coefficients of cos wt gives... 

Other potential uses For example, applications as a solvent in separations and reactions, expanding markets for chemicals from carbon dioxide, enhanced recovery of oil, natural gas, and coal bed methane. 

In the same year, Sames [49] reported the C- H/C-X coupHng of indoles and aryl iodides under palladium catalysis. These reactions expanded the substrate scope of direct arylation of indoles and used lower catalyst loadings when compared to Ohta s result (Scheme 17.11). 

Additional reactivity of 2-TST (1) such as metalation, reaction with different electrophiles, and cross-coupling reactions expands the applicabUity of this reagent to the synthesis of substituted thiazoles. 

After publication of the above works, the number of contributions on the OCM reaction expanded greatly. Many metal oxide catalysts have been tested for this reaction. The catalysts can be grouped as (i) oxides of groups IV and V metals,... 

Palladium-catalyzed Functionalization at N-/. Palladium-mediated cross-coupling of variedly substituted indazoles using dialkylphosphino biaryl ligands delivers excellent yields for N- arylation products. The reaction conditions are tolerant toward the presence of electron-withdrawing nitro and cyano substituents at the 6-position of benzopyrazole. Importantly, the use of aryl chlorides and bromides in these coupling reactions expands the available scope of aryl halides available for coupling at the A -1 position (eqs 6-8). 

Determine whether the equality of Eq. 10.15 holds for a first-order reaction. Expand Rg in a Taylor series around T and C. 

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