Water, bond dissociation energy reaction

Use the bond dissociation energies in Table 7.1 to calculate an approximate AH° (in kilojoules) for the industrial synthesis of isopropyl alcohol (rubbing alcohol) by reaction of water with propene, as shown at the top of the next column. 

Many compounds [olehns, alcohols, and carboxyhc acids (or other carbonyl chemistry)] will undergo dimerization reactions. Figure A15-7 shows how carboxylic acids can react with an alcohol to form a dimer [6] (note that it should be loss of water and not carbon dioxide). In RP-UPLC under basic conditions, the elution order would be dihunisal in its ionized form < descarboxydiflunisal < the dimer. Indoles have been shown to dimerize under acidic conditions, and phenols have shown to dimerize under free radical initiated oxidative conditions, usually ortho-phenols [1]. Due to the low bond dissociation energy of the benzylic C-H bond and ease of radical formation, dimerization can occur at the benzylic center. Nalidixic acid undergoes dimerization under thermolysis conditions to produce a dimeric structure [26]. 

The bond dissociation energies of the alkali metal hydroxides have been the subject of a number of investigations (1[ -4) in recent years. The majority of this work has involved equilibrium studies on the reaction A(g) + HpO(g) = AOH(g) + H(g), where A is an alkali metal, in hydrogen-oxygen-nitrogen flames containing water. In the case of NaOH, data are summarized below ... 

In aqueous solution, reaction (71) does not occur owing to the high bond dissociation energy of the water molecule. Reaction (70)... 

The cr-substituent effects and solvent effects (extended Grunwald-Winstein equation) for solvolyses of / -X-substituted benzoyl chlorides (X = OMe, Me, H, and Cl) in 97% wt/wt hexafluoroisopropanol/water was explained by two competing pathways. Plots of log k versus a were consistent with a cationic path and explained by an 5 n2-5n1 spectrum of mechanism. Electron-donating groups favoured the reaction and values of p increased in the order AcOH < HCO2H < TEE < HFIP. A benzoyl cation intermediate was trapped in hexafluoroisopropanol. Ab initio calculations of heterolytic bond dissociation energies of various chloro- and fluoro-substituted and other benzoyl chlorides were correlated with log k for solvolyses... 

The use of blackbody IR radiation to dissociate isolated gaseous ions within the cell of an FT-ICR mass spectrometer was first demonstrated by McMahon and co-workers for the dissociation of small, weakly bound ion clusters of the type H30 (H20) , Cl (H20) , and H3O ((CH3)20)(H20) . These ions were found to readily lose neutral water molecules at ambient temperature. At the typical reaction temperatures achievable with BIRD, dissociation of the noncovalent interactions within ionic clusters (e.g., ion-solvent interactions) that have bond dissociation energies of 70-200 kJ mol ... 

The reaction can take place at anode potentials largely lower than the thermodynamic potential of water oxidation to oxygen (1.23V/SHE under standard conditions). However, in order to achieve the dissociative activation of water (1.7), electrocatalytic electrodes are needed. In fact, the dissociative adsorption of water can be achieved only at electrodes (M) on which the bonding energy of M-OH and M-H exceeds the dissociation energy of water to H + HO. This is the case of Pt-Ru-based electrodes on which water activation can be achieved at 0.2-0.3 V/SHE. 

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