Methyl-cyclohexane

A METHYL CYCLOHEXANE 273-343 1 4687E4-02 -8.3627E403 4. 1169E-02 -2.3246E401 -1.6077E-05... 

Allene (prodiene) [463-49-0] M 40.1, m -146 , b -32 . Frozen in liquid nitrogen, evacuated, then thawed out. This cycle was repeated several times, then the allene was frozen in a methyl cyclohexane-liquid nitrogen bath and pumped for some time. Also purified by HPLC. [Cripps and Kiefer Org Synth 42 12 1962.]... 

Toluene is commonly used. It can be dried by molecular sieves or direct distillation from calcium hydride into the reaction flask. Solvent stored over calcium hydride for several days is usually sufficiently dry to decant directly into the reaction flask, but distillation gives more consistent results. Any solvent with a boiling point sufficiently high to melt sodium is satisfactory. The submitters have also used methyl-cyclohexane and xylene in acyloin condensations. After the sodium is dispersed, the high-boiling solvent can be removed and replaced with anhydrous ether (as noted by the submitters) or can be retained and used in combination with ether (checkers). 

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

These heat of formation parameters may be considered as shifting the zero point of Fpp to a common origin. Since corrections from larger moieties are small, it follows that energy differences between systems having the same groups (for example methyl-cyclohexane and ethyl-cyclopentane) can be calculated directly from differences in steric energy. 

By oxidation with chromic acid, this is converted into cyclohexanone-3-carboxylic acid, in which the —CH. OH— group is converted into the —CO— group. This is converted into its ethyl ester and treated with magnesium methyl iodide, and the product, on hydrolysis, yields l-methyl-cyclohexane-l-ol-3-carboxylic acid, which is converted byhydro-bromic acid into 1-bromo-l - methyl - cyclohexane - 3 - carboxylic acid. When this is digested with pyridine, hydrobromic acid is eliminated and yields l-methyl-A -cyclohexane-3-carboxylic acid of the formula—... 

The active variety of the terpene d-sylvestrene has been prepared synthetically by preparing the methyl-cyclohexane-carboxylic acid described above, and recrystallising its brucine salt. The acid contains a small quantity of the A acid, although the A variety predominates. The A acid was resolved by the brucine crystallisations, and an acid of rotation -t- 90° obtained. The synthetic process was then proceeded with, and the resulting terpene was found to be d-sylvestrene, having a rotation of -1- 66°. 

The oil that separates is extracted with ether, the extract dried over anhydrous sodium sulfate and then evaporated at reduced pressure. The residue is dissolved in boiling benzene (75 ml) treated with decolorizing charcoal, filtered, treated with boiling cyclohexane (275 milliliters) and cooled to give 22.3 grams of 2,3-dichloro-4-butyrylphenoxyacetic acid. After several recrystallizations from a mixture of benzene and cyclohexane, then from methyl-cyclohexane, next from a mixture of acetic acid and water, and finally from methylcyclo-hexane, the product melts at 110° to 111°C (corr). 

Assume that you have two unlabeled samples, one of methyl cyclohexane and the other of ethylcyclopentane. How could you use mass spectrometry to tell them apart The mass spectra of both are shown in Figure 12.6. 

II x. h3c sch3 Methyl thioacetate II ch3ch2ch2 sch2ch3 Ethyl butanethioate (J Methyl cyclohexane-... 

H3C- COOH Li[AlH4] cis-4-Methyl-l-hydroxy- methyl-cyclohexan 90 90-91 12 11... 

Oxo-l-methyl-cyclohexan-carbonsaure-athylester wird unter milden Bedingungen zu 2-Hydroxy-l-methyl-cyclohexan-carbonsaure-dthylester reduziert13 ... 

---