Acetone hydrate

Even if both bromines were replaced by hydroxyl groups, the resulting diol (acetone hydrate) would lose water since acetone does not form a stable hydrate. 

FIGURE 16.29 The magnirnde of the equilibrium constant (A) depends on the relative energies of the carbonyl compounds and their hydrates. We know that for acetaldehyde the energies of hydrate and aldehyde are comparable, because A" 1. Acetone is more stable than acetaldehyde and formaldehyde is less stable. Steric factors make the acetone hydrate less stable than the acetaldehyde hydrate. By contrast, the formaldehyde hydrate is more stable than the acetaldehyde hydrate. The equilibrium constants reflect these changes. 

FIGURE 3.2 Br0nsted plot for the dehydration of acetone hydrate in acetone, catalyzed by acid. The logarithm of the catalytic rate constant is plotted versus the negative of the dissociation constant of the acid. Points are shown for 32 carboxylic acids and 15 phenols. The point labeled 47 represents 2,4-dinitrophenol. Acids of other types (e.g., oximes) fell much further off the line (see Section 3.6.3). Source Bell and Higginson (1949) by permission of the Royal Society of London. 

CliHigByCoNi, 2,3-Di-r -cyclopentadienyl-10-carba-(2,3)(nickelaco-balta)decaborane(8)(Ni-Co), 44B, 576 Cl1H30B18Cs2Fe20e, Dicaesium di-M carbonyl-bis(tt-(3)-1,2-dicarbo-llylcarbonyliron) acetone hydrate, 35B, 432 C12H9BO2, 2-Phenyl-l,3,2-benzodioxaborol, 40B, 587 Cl2H10BCI2N, Dichloro(diphenylamino)borane, 41B, 708... 

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