Cyclohexanol acidity

The selective oxidation of saturated hydrocarbons is a reaction of high industrial importance. Besides a variety of other oxidants, hydrogen peroxide as a very clean oxidant has also been used for these purposes . As an example, in 1989 Moiseev and coworkers reported on the vanadium(V)-catalyzed oxidation of cyclohexane with hydrogen peroxide (Scheme 146) . When the reaction was carried out in acetic acid cyclohexanol and cyclohexanone were formed, bnt conversions were very poor and did not exceed 13%. Employing CF3COOH as solvent, complete conversions could be obtained within 5 min-ntes. Here, cyclohexyl trifluoroacetate was the main product (85% of the products formed) resulting from the reaction of cyclohexanol (the primary product of the oxidation) with CF3COOH. 

Phosphorus trichloride. Aluminum chloride. Methyl chloride. Hydrochloric acid. Hydrofluoric acid, Cyclohexanol, Silica gel. Isopropyl ether Phosphorus trichloride. Aluminum chloride. Methyl chloride. Hydrochloric acid. Sodium fluoride, Cyclohexanol, Silica gel. Isopropyl ether. Toluene Phosphorous trichloride. Methyl disulfide. Methyl iodide. Toluene, Sodium fluoride. Isopropyl alcohol... 

H. Chihara. Kagaku no RySiki 10, 31-8 (1956). Calculation AH from sublimation, acetic acid, cyclohexanol, diketopipera-zine, dimethylgloxime. 

Adipic acid may be obtained from cyclohexanol by oxidation with hot nitric acid. Cyclohexanol is prepared from phenol by hydrogenation. Thus the entire series of reactions represents (a) the change of an aromatic six-carbon compound to an alicyclic one (6) the opening of a six-carbon ring to an open chain compound (c) the cyclization of an open chain compound. The object of the present experiment is to illustrate this last step through the preparation of cyclopentanone from adipic acid. 

Oligosaccharides in combination with phenols may also be removed intact by careful hydrolysis with acid. Thus, when rutin is heated with 10% aqueous acetic acid, it yields rutinose. Dilute mineral acids can, for example, be used for the removal of sophorose from kaempferol 3-sophoroside, " and of gentiobiose from p-hydroxyphenyl 9-gentiobio-side. A comparison of the use of formic acid-cyclohexanol and hydrochloric acid-acetic acid for the partial hydrolysis of glycosides has been made by Chandler and Harper. There appears to be no general rule governing the use of these acids. 

Another way of explaining this difference in acidity is to say that the activation energy (the energy differential between the reactants and the transition state of the reaction) for phenol s ionization is less than that of cyclohexanol s loss of a proton. NaOH is a base that will receive a proton from phenol but not from the weaker acid cyclohexanol. Experimentally, this means that the phenoxide salt will be in the aqueous layer of an ethereal-aqueous mixture and will easily be removed. Subsequent protonation will yield phenol. 

Cyclohexane, 1-trifluoromethyl-1,2,2,3,3,4,4,5,5,6,6-undecafluoro-. See Perfluoromethylcyclohexane Cyclohexanoic acid. See Cyclohexanecarboxylic acid Cyclohexanol... 

Chlorinated n-paraffins (C6-C18) Chlorotrifluoroethylene polymer Cresylic acid Cyclohexanol 1,10-Decanediol Dehydroacetic acid Diamyl phenol Diamyl phthalate Dibutyltin dilaurate Dibutyltin maleate... 

When heated with sulfuric or phosphoric acid, cyclohexanol, CsHnOH, is converted to cyclohexene, CsHjo. Ball-and-stick models of cyclohexanol and cyclohexene are shown here. The balanced chemical equation for the reaction is shown below. 

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