Ketones thermodynamic data

B. D. Smith and R. Srivastava, Thermodynamic Data for Pure Compounds Part A.. Hydrocarbons and Ketones, Elsevier, Amsterdam, the Netherlands, 1986. T. Boubhk, V. Eried, and E. Hala, The Hapour Pressures of Pure Substances, 2nd ed., Elsevier, Amsterdam, the Netherlands, 1984. 

Table 8.5 lists the enthalpies for a series of isodesmic reactions involving conversion of carbonyl derivatives to the methyl ketones. The A// of the reactions is given both from thermodynamic data and as calculated at the MP3/6—3H--I-G level. These... 

To test theory one must work with solutions for which adequate thermodynamic data exist. Figure 7 contains the state diagram of the same polystyrene with mixtures of methyl isobutyl ketone and Figure 8 with toluene. The similarity... 

Flash photolysis has provided a wealth of kinetic and thermodynamic data for tautomerization reactions. Equilibrium constants of enolization, KE, spanning a range of 30 orders of magnitude, have thereby been determined accurately as the ratio of the rate constants of enolization, kE, and of ketonization, kK. Nowadays, tautomerization constants KE can be predicted with useful... 

Thus, in the pH range 4 6, the triplet enol tautomer 12 is thermodynamically more stable than the triplet ketone 11. The spectroscopic and thermodynamic data are summarized in Figure 5.8. When the enol 12 decays to the ground state, it becomes an extremely strong acid and it immediately protonates water to give the anion 11. The pKa of enol 12 in the ground state was estimated at —8.5 on the basis of calculations for the equilibrium between 11 and 12 and the measured triplet... 

According to these thermodynamic data, significant conversion can be obtained for the condensation of acetone with formaldehyde. Diacetone alcohol can be formed in low yield only and has a lower tendency to dehydrate than the aldols formed from benzaldehyde. The energy balance of the process is so displaced by the formation of water that the unsaturated ketone is usually obtained. The... 

Smith, B. D. Srivastava, R. "Thermodynamic Data for Pure Compounds, Part A. Hydrocarbons and Ketones," Elsevier Amsterdam, 1986. (Thermodynamic properties). 

The Thermodynamic Properties of Pure Compounds. Part B Halogenated Hydrocarbons and Ketons, Physical Data Series, Vol. 25. Elsevier, Amsterdam. 

TEMPO+ abstracted hydride anions from the hydrides of aldehydes and ketones in acetonitrile without any side products. The hydride affinity of aldehydes and ketones in acetonitrile was defined as fhe enthalpy change of the aldehydes and ketones. Several conclusions regarding the hydride-accepting abilities of aldehydes and ketones, based on thermodynamic data, were listed." " ... 

The applications are so many that it is difficult to select a few. Limiting the attention to some basic issues, one may mention a recent study using density functional theory and molecular orbital G3(MP2) method to provide thermodynamic data for the analysis of the photochemistry of ketones on Ti02. The bond energies of a range of gem-diols, RR C(OH)2, have been used as models for the binding to the titania surface (see Scheme 24). ... 

Recently, an ab initio 6-31 G basis set calculation reaffirmed that phenol is significantly more stable than both 2,4- and 2,5-cyclohexadienone. Total electronic energies at 0 K and thermodynamic parameters were calculated for phenol, 2,4-cyclohexa-dienone, and 2,5-cyclohexadienone. Energy calculations were performed using the restricted Hartree— Fock (RHF) and second-order Moller—Plesset formalisms on the RHF optimized geometries. The study has shown the following (i) phenol is more stable than the two ketones by around 18 kcal/mol (ii) the ketone with the C-sp para to the carbonyl is slightly less stable than the one with the C-sp ortho to the carbonyl (iii) thermodynamic data calculated for the ketones versus the enol forms for the three species confirm the already known fact that phenol is more stable in the enolic form (Scheme 16). 

Recent applications of the theory have been made for calculating the contribution the formation of a cavity gives to the free energy of transfer of a series of isomeric ketones(134), or various other solutes(132), from H2O to D2O, for the studies of solubility of many apolar gases in water and other polar solvents(135), for comparing the experimental thermodynamic data for the solution of rare gases(51), or some perfluorocarbon gases(136), in water at various temperatures with data calculated by means of the SPT. In a tentative made to extend the theory at aqueous solutions where solute-solute interactions have to be considered and hydrophobic interactions are operative, it has been shown that the dependence of the partial molar volumes and enthalpies of hard-sphere solutes in water on concentration and temperature are due to the anomalous trends the 63/6P and 63/6T (3 coefficient of isothermal compressibility) of pure water present, rather than to the solute structural effects(137). 

Smith BD, Srivastava R (1986) Thermodynamics data for pure compounds Part A hy-drocarbones and ketones. Elsevier Science Publ., Amsterdam 14... 

Pyrolyses of formates, oxalates and mellitates yield CO and C02 (H2, H20 etc.) as the predominant volatile products and metal or oxide as residue. It is sometimes possible to predict the initial compositions from thermodynamic considerations [94], though secondary reactions, perhaps catalyzed by the solids present, may result in a final product mixture that is very different. The complex mixtures of products (hydrocarbons, aldehydes, ketones, acids and acid anhydrides) given [1109] by reactants containing larger organic groupings makes the collection of meaningful kinetic data more difficult, and this is one reason why there are relatively few rate studies available for the decompositions of these substances. 

It is clear that kinetic effects must be utilized in the design of a process to make the commercially available Form A, because it is never the most thermodynamically stable form. Information from the literature and patents in reference [14] indicates that Form A can be successfully isolated from Acetonitrile, Acetone, Methyl isobutyl ketone, Toluene, the C2 to C4 alkenols, Ethanol, Methanol and Propan-2-ol. In these solvents it is likely that solvation is favourable to the nucleation rate of Form A or detrimental to crystal growth of the other forms, or both. For a new development compound there should be similar solvent interaction data available from polymorph screening experiments. 

A large number of studies have addressed the condensation of cyclic ketones with both aliphatic and aromatic aldehydes under conditions that reflect both thermodynamic (cf. Table 2) and kinetic control of stereochemistry. The data for cyclohexanone enolates are summarized in Table 8. Except for the boryl enolates cited (6), the outcome of the kinetic aldol process for these enolates... 

Imines derived from macrocyclic ketones (C10 to C 15 ) and (- )-(S)-a-(methoxymcthyl)benzene-ethanamine are successfully deprotonated using LDA ( —25 JC. THF. 1 h)9. In contrast to azaenolates of C0- to C8-membered cyclic ketones, which show only E geometry, Z-isomers are observed with macrocyclic imines. As evident from H-NMR data, azaenolates of cyclodecanone imines generated under these conditions are a mixture of E- and Z-isomers (33 66), whereas azaenolates of cyclododecanone and cyclopenladecanone imines arc formed as the pure. E-isomers (see Table 3). Upon heating the solutions of metalated imines to reflux for 1 hour, complete isomerization to the thermodynamically more stable Z-isomers occurs. 

Of interest is a comparison of a-methoxy with a-hydroxy substituents. The a-hydroxy carbenium ions correspond to protonated ketones and their pAR values may be derived from a combination of a hydration equilibrium constant and a pfor protonation of the ketone, as illustrated by the thermodynamic cycle based on acetophenone in Scheme 15.I37,I3X Corresponding data are available for benzaldehyde138,139 and acetone70,140,141 and lead to the values of... 

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