Exam 4: Organic Compounds: Cycloalkanes and Their Stereochemistry

Exhibit 4-2 For each substituted cyclohexane below,draw its ring-flip isomer.Circle the most stable conformation. -Refer to Exhibit 4-2.

Draw the two stereoisomers of 1,3-dibromocyclobutane.

(-)-Menthol can be isolated from the peppermint plant and is responsible for the characteristic flavor and taste of peppermint.The structure of (-)-menthol is: On the chair template provided below,draw the two chair conformations that are in equilibrium for (-)-menthol.

Exhibit 4-3 The following question(s) refer to the structure of camphor shown below. -Refer to Exhibit 4-3.Circle all bridgehead carbons in camphor.

Draw: cis-1-sec-butyl-2-ethylcyclopentane

Name:

In general,5-alkyl substituents in 1,3-dioxane exhibit a smaller equatorial preference than they do in cyclohexane.To what might you attribute this observation?

In cyclopropane,which of the following strain types would be the least important in determining the overall energy?

Circle all bridgehead carbons in the following structure.

D-Pinitol is an interesting hexahydroxy cyclohexane,whose structure is shown below. On the templates provided,draw the two chair conformations that are in equilibrium for D-pinitol.Circle the most stable conformation.

Exhibit 4-1 Refer to the structure below to answer the following question(s): -Refer to Exhibit 4-1.Which of the labeled bonds in the structure are equatorial bonds?

Exhibit 4-4 Label each pair of compounds below as: -_____

Exhibit 4-4 Label each pair of compounds below as: -_____

Draw 7 constitutional isomers of a cycloalkane with the formula C₆H₁₂.Name each of the isomers you drew.

Consider the following table. Based on the data in the table,which of the following compounds would have the largest strain energy?

Draw: 1-chloro-2-isopropylcyclopentane

The energy difference of 3.8 kJ/mol between gauche and anti butane corresponds to an equilibrium constant,K_eq,of approximately 1.9.Calculate the percentage of each conformer at equilibrium.