Conformers of Disubstituted Cyclohexanes

The chair conformer of fluorocyclohexane is 0.25 kcal/mol more stable when the fluoro substituent is in an equatorial position than when it is in an axial position. How much more stable is the anti conformer than a gauche conformer of 1-fluoropropane considering rotation about the C-l-C-2 bond  

Using the data in Table 3.9, calculate the percentage of molecules of cyclohexanol that have the OH group in an equatorial position at 25 °C. 

If a cyclohexane ring has two substituents, we must take both substituents into account when predicting which of the two chair conformers is more stable. Let s use 1,4-dimethylcyclohexane as an example. 

First of all, note that there are two different dimethylcyclohexanes. One has both methyl substituents on the same side of the cyclohexane ring (both point downward)— it is called the cis isomer (cis is Latin for on this side ). The other has the two methyl substituents on opposite sides of the ring (one points upward and one points downward)—it is called the trans isomer (trans is Latin for across ). 

The cis isomer of a disubstituted cyclic compound has its substituents on the same side of the ring. 

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Problem-Solving Strategy Drawing Chair Conformations 116 3-14 Conformations of Monosubstituted Cyclohexanes 117 3-15 Conformations of Disubstituted Cyclohexanes 120... 

DRAWING BOTH CHAIR CONFORMATIONS OF DISUBSTITUTED CYCLOHEXANES... 

SkillBuilder 4.12 Drawing Both Chair Conformations of Disubstituted Cyclohexanes... 

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