Conductance Data among Solvents

Among the several screened cinchona derivatives, (DHQ)2AQN 6 was selected for a full optimization of the conditions (solvent and temperature). The reaction was carried out in DMF with a combination of benzoyl fluoride and ethanol as a latent source of HF. Enantioselectivities up to 92% ee were obtained with tetralones trimethylsilyl enol ethers Sa-d using 10 mol% of organocatalyst 6 (Table 7.1, entries 1-4). Indanone silyl enol ethers Se-g afforded the corresponding ketones 7e-g with lower selectivities (64—74% ee, Table 7.1, entries 5-7) while the 2,2,6-trimethyl-cyclohexanone was obtained with only 58% ee, the reaction being conducted at — 10 °C (data not shown in Table 7.1). 

Among other subjects the influence of the conditions, in which the polymerization process is conducted, on the supramolecular structure of the polymer formed is discussed in studies40-42. Using these data the researchers analyzed the impact of polymerization kinetics on the polymers supramolecular structure and formulated the basic principles for controlling the structure of the polymer in the course of its synthesis. They also proposed a new thermodynamic approach for controlling supramolecular structures. The possible uses of this method are demonstrated in the polymerization of trioxane and triethylamine in different solvents and at different monomer concentrations. The purpose of this approach and the manner in which it differs from the conventional kinetic approach are roughly illustrated by the scheme in Fig. 5. 

This paper refers, among others, to some similarities inherent in the course of some normalized graphs plotted on the basis of titration curves obtained from PT and CT made for the pair of solutions titrand (solution titrated, D), and titrant (titrating solution, T), containing the same acid HL, with identical concentration, C mol/L, in D and T the only difference in D and T lies in the solvent composition that affects the changes in pH and conductivity of D+T mixture it is the most principal novelty of the titrimetric procediue. The results obtained from PT and CT will be modeled, for comparative purposes, with use of polynomial functions. However, the modehng is made only to compare the experimental data obtained at different values of (a) initial volumes (Vq) of D and (b) increments (AV) of T applied in PT and CT. Furthermore, after this introductory step, we aimed to apply the models with minimal or none additional parameters needed to compare the data in PT and CT. 

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