Page 71 - Pharm.Org.Chem-I 02-06-05-101

The most stable conformation of
substituted chclohexanes:

e.g. methylcyclohexane

H HCH3(axial) HH
H HH

HH HH H H H CH3 (equitorial)
HH HH
H (1) H H (2) H

(less stable) (a) (more stable by 7.5 kJ mol−)

H HCH3 HH
HH
HH HH
H H HH H CH3
H H
H H
(b) H H

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B-Configurational isomerism in cyclohexane:

1,4-Dimethylcyclohexane

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