7-Methyl-3- cyclohexanol

Two stereoisomers of 1 bromo 4 methylcyclohexane are formed when trans 4 methyl cyclohexanol reacts with hydrogen bromide Write structural formulas or make molecular mod els of... 

Methyl chloroform, see 1, -l, -1 -Trichloroethane Methyl chloroformate Methyl cyanide, see Acetonitrile Methyl cyclohexane a-Methyl cyclohexanol 2-Methyl cyclohexanone... 

The next step was to convert cyclohexanone-4-carboxylic acid into l-methyl-cyclohexanol-4-carboxylic acid, and this is readily accomplished by heating the ester of the ketonic acid with magnesium methyliodide in the usual manner—... 

The mechanisms of these acid-catalyzed epoxide openings are more complex than they at first appear. They seem to be neither purely SN1 nor SN2 but instead to be midway between the two extremes and to have characteristics of both. Take the reaction of 1,2-epoxy-l-methylcyclohexane with HBr shown in Figure 18.2, for instance. The reaction yields only a single stereoisomer of 2-bromo-2-methyl-cyclohexanol in which the —Br and —OH groups are trans, an S 2-li.ke result caused by backside displacement of the epoxide oxygen. But the fact that Br attacks the more hindered tertiary side of the epoxide rather than the less hindered secondary side is an SN1 -like result in which the more stable, tertiary carbocation is involved. 

Methyl cyclohexanols Propyl ketones Terminal aliphatic epoxides,... 

Depending on the orientation of substituents, the disubstituted cyclohexanes can be either equatorial-axial or diequatorial. This is illustrated with 2-methyl cyclohexanol. It exists in two stereoisomeric forms and each of which has two conformations which are readily interconvertible. 

Let us again take the case of methyl cyclohexanol, but with substituents in 1, 3 positions. Two stereoisomers of this compound are known. 

The conformational equilibria of various methylated cyclohexanols have been... 

Oxidation of tertiary alcohols by lead tetraacetate gives alkyl radicals by /3-scission of the initially formed alkoxy radicals. The reaction has been used to alkylate protonated heteroaromatic bases using 1-methyl-cyclohexanol. (Scheme 4). 

The data in Table 2 show the potential of the Na2B407 based catalyst system tested over large number of representative alcohols. The primary alcohols were oxidized to the corresponding aldehydes at complete conversion of the alcohol and at 90-93% selectivity. The only by-products observed were the corresponding acid and minor amounts of the symmetrical ester (Entry 2, 3). Benzyl alcohol was quantitatively converted to benzaldehyde. The secondary alcohols, 4-methyl cyclohexanol and 4-methylpentanol were converted to the corresponding ketones at room temperature. 

Methyl cyclohexanols, flash point not more than 60.5 degrees C 2617... 

Two hundred seventy milliliters (497 g., 4.86 moles) of 96% sulfuric acid (Note 1) is poured into a 1-1. three-necked flask equipped with a paddle stirrer driven by a powerful motor, a dropping funnel with a gas by-pass, and a thermometer that dips into the acid. The reaction mixture is stirred vigorously (Note 2) and maintained at 15-20° by means of a cooling bath as 3 ml. of 98-100% formic acid (Note 3) is added dropwise. Under the same conditions, a solution of 28.5 g. (0.25 mole) of 2-methyl-cyclohexanol (Note 4) in 46 g. (1.00 mole) of 98-100% formic acid is added in the course of 1 hour. The reaction mixture foams during the additions. The mixture, which is a very light cream color, is stirred for 1 hour at 15-20° and then is poured with stirring onto 1 kg. of crushed ice in a 4-1. beaker. The carboxylic acid separates as a white solid. 

The checkers used o-Methylcyclohexanol, available from K K Laboratories, Jamaica, New York. They redistilled it before use b.p. 70-80° (20 mm.), n2Sd 1,4617. 3- or 4-Methyl-cyclohexanol can be used in place of 2-methylcyclohexanol, or mixtures of the three can be used. 

NUCLEOPHILIC HYDROXY-METHYLATION OF CARBONYL COMPOUNDS 1-(HYDROXY-METHYL)CYCLOHEXANOL... 

Let s look at a very simple one-step synthesis to illustrate this difference. Given die following set of reactants, methyl cyclohexanol and chromic acid in acetone, it is very easy to write the product as 4-methylcyclohexanone ... 

One useful example is the dehydration of the secondary alcohol 2-methyl-cyclohexanol, which yields a mixture of two regioisomers in which the more highly substituted alkene predominates in this case the mixture may be separated by careful fractional distillation (cognate preparation in Expt 5.12). 

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