Tert-Butylcyclohexane

A tert butyl group is so large that tert butylcyclohexane exists almost entirely in the conformation m which the tert butyl group is equatorial The amount of axial tert butylcyclohexane present is too small to measure... 

Compare energies for equatorial and axial chair conformers for methylcyclohexane, R = Me, and tert-butylcyclohexane, R = CMe3. Which is more stable in each molecule Use equation (1) to calculate the ratio of major to minor conformers for each system at 298 K. Which molecule shows a larger preference Why (Hint Compare nonbonded interactions and/or geometrical distortions in the higher-energy conformers that are absent in the lower-energy conformers.)... 

Which is more stable, the equatorial or axial chair conformer of i-propylcyclohexane, R=CHMe2 Calculate the ratio of major to minor conformers at 298 K. Is it more like that found for tert-butylcyclohexane or for methylcyclohexane Why ... 

Problem 11.19 Which isomer would you expect to undergo E2 elimination faster, f/uus-l-bromo-4-fr7t-butyJcyclohexane or ds-l-bromo-4-tert-butylcyclohexane Draw each mole-, cule in its more stable chair conformation, and explain your answer. 

The conformation of tert-butylcyclohexane with tert-butyl group equatorial is more than 21 kJ mol-1 more stable than the axial form. 

Allinger (p. 305) found the energy difference between cis- and trans-, i-d -tert-butylcyclohexane to be 5.9 kcal/mole, and considers that this value represents the energy difference between the chair and twist-boat forms of cyclohexane. Defend Allinger s position. 

Information concerning solubilization of hydrocarbons in ionic surfactant micelles was obtained from 2H NMR relaxation and H NMR paramagnetic relaxation measurements. The location of the hydrocarbons (benzene naphthalene, triphenylene cyclohexane, cyclododecane and tert-butylcyclohexane) in micelles... 

T rimethylcyclohexane tert-Butylcyclohexane n-Butycyclopentane n-Butycyclohexane Other Cycloparaffins... 

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