Alcohols inductive effects

Carboxylic acids are weak acids and m the absence of electron attracting substituents have s of approximately 5 Carboxylic acids are much stronger acids than alcohols because of the electron withdrawing power of the carbonyl group (inductive effect) and its ability to delocalize negative charge m the carboxylate anion (resonance effect)... 

Inductive effects (Section 16.4) are also important in determining alcohol acidities. Electron-withdrawing halogen substituents, for example, stabilize an alkoxide ion by spreading out the charge over a larger volume, thus making the alcohol more acidic. Compare, for example, the acidities of ethanol (p/tcrt-butyl alcohol (p/

Indolmycin, biosynthesis of, 864 Inductive effect. 37, 562 alcohol acidity and. 604 carboxylic acid strength and. 758 electronegativity and, 37 electrophilic aromatic substitution and, 562... 

The use of ethanol as an achiral auxiliary gave the adduct 53 with 55% ee, while neopentyl alcohol and methanol gave 96 and 87% ee, respectively. These results suggested that the achiral alcohol might exert a steric effect on the stereoselectivity. However, the increase in enantioselectivity from 55% to about 96% when 2,2,2-trifluoroethanol (TFE) was used instead of ethanol indicates a possible significant inductive effect also. Good enantioselectivities were also obtained with carboxylic acids and phenols. 

The inductive effect of the imidazole substituents on the transphosphorylation of alcohols and amines with the following spin-labeled phosphoric imidazolides is discussed in reference [190]. 

This enhanced reactivity of fluoromethyl cyanide is undoubtedly due to the inductive effect of the fluorine atom which produces an electron deficit on the carbon atom linked to the nitrogen, and presumably increases still further the polarity of the carbon-nitrogen bond, so that the electron displacements can be pictured as (IX). The increased polarity of the carbon-nitrogen bond will obviously facilitate polar addition of hydrogen chloride and alcohols (or phenols). 

Also other Type B and C series from Table II are consistent with the above elimination mechanisms. The dehydration rate of the alcohols ROH on an acid clay (series 16) increased with the calculated inductive effect of the group R. For the dehydrochlorination of polychloroethanes on basic catalysts (series 20), the rate could be correlated with a quantum-chemical reactivity index, namely the delocalizability of the hydrogen atoms by a nucleophilic attack similar indices for a radical or electrophilic attack on the chlorine atoms did not fit the data. The rates of alkylbenzene cracking on silica-alumina catalysts have been correlated with the enthalpies of formation of the corresponding alkylcarbonium ions (series 24). Similar correlations have been obtained for the dehydrosulfidation of alkanethiols and dialkyl sulfides on silica-alumina (series 36 and 37) in these cases, correlation by the Taft equation is also possible. The rate of cracking of 1,1-diarylethanes increased with the increasing basicity of the reactants (series 33). 

Oxygen is so electronegative that inductive effects from substituents have rather less influence on basicity than they would in similar nitrogen compounds. Alcohols are somewhat less basic than water, with ethers weaker still. 

Although an alteration in the specific inductive capacity of the double layer may be effected by the selective adsorption of the non-electrolyte yet such an explanation is evidently by no means adequate thus we find 1500 millimols. of ethyl alcohol as effective as 70 millimols. of isoamyl alcohol, whilst the dielectric capacities of water and the two alcohols stand in the ratio 81 20 8 5 7 again the anomalous behaviour of di- and tetravalent cations as noted by Efruyt and van Duin is not explicable on this hypothesis. 

Another effect to be considered is an inductive effect although the total charge on the complex molecule, [Cr(HO-A)2] , is negative, it is possible that chromium (III) exerts its effect on the free OH group, increasing the acidity of the alcohol proton. Acidic alcohols, such as phenol, may be acetylated readily, so that this does not seem to be a plausible explanation for the very slow ketene reaction. 

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