For rotation about the C-3---C-4 bond of 2-methylhexane, do the following:

c. About which other carbon–carbon bonds may rotation occur?

d. How many of the carbon–carbon bonds in the compound have staggered conformers that are all equally stable?

Draw all the isomers that have molecular formula C₅H₁₁Br. (Hint: There are eight.)

a. Give the systematic name for each of the isomers.

Draw all the isomers that have molecular formula C₅H₁₁Br. (Hint: There are eight.)

b. Give a common name for each isomer that has a common name.

Draw all the isomers that have molecular formula C₅H₁₁Br. (Hint: There are eight.)

c. How many of the isomers are primary alkyl halides?

d. How many of the isomers are secondary alkyl halides?

e. How many of the isomers are tertiary alkyl halides?

What is each compound’s systematic name?

g.

h.

Draw the two chair conformers for each of the following and indicate which conformer is more stable:

b. trans-1-ethyl-2-methylcyclohexane

Draw the two chair conformers for each of the following and indicate which conformer is more stable:

c. trans-1-ethyl-2-isopropylcyclohexane

Draw the two chair conformers for each of the following and indicate which conformer is more stable:

d. cis-1,2-diethylcyclohexane

Draw the two chair conformers for each of the following and indicate which conformer is more stable:

e. cis-1-ethyl-3-isopropylcyclohexane

Draw the two chair conformers for each of the following and indicate which conformer is more stable:

f. cis-1-ethyl-4-isopropylcyclohexane

Why are lower molecular weight alcohols more soluble in water than higher molecular weight alcohols?

Draw a potential energy diagram for rotation about the C¬C bond of 1,2-dichloroethane through 360°, starting with the least stable conformer. The anti conformer is 1.2 kcal/mol more stable than a gauche conformer. A gauche conformer has two energy barriers, 5.2 kcal/mol and 9.3 kcal/mol.

Draw the conformer that is present in greatest concentration.

How much more stable is the most stable staggered conformer than the most stable eclipsed conformer?

How much more stable is the most stable staggered conformer than the least stable eclipsed conformer?

For each of the following compounds, determine whether the cis isomer or the trans isomer is more stable.

a.

b.

c.

How many ethers have molecular formula C₅H₁₂O? Draw their structures and give each a systematic name. What are their common names?

Draw the most stable conformer of the following molecule. (A solid wedge points out of the plane of the paper toward the viewer. A hatched wedge points back from the plane of the paper away from the viewer.)

What is each compound's systematic name?

a.

What is each compound's systematic name?

b.

What is each compound’s systematic name?

c.

d.

What is each compound’s systematic name?

e.

f.

Calculate the energy difference between the two chair conformers of trans-1,2-dimethylcyclohexane.

The most stable form of glucose (blood sugar) is a six-membered ring in a chair conformation with its five substituents all in equatorial positions. Draw the most stable conformer of glucose by putting the OH groups and hydrogens on the appropriate bonds in the structure on the right.

What is each compound’s systematic name?

e.

f.

Explain the following:

a. 1-Hexanol has a higher boiling point than 3-hexanol.

One of the chair conformers of cis-1,3-dimethylcyclohexane is 5.4 kcal/mol less stable than the other. How much steric strain does a 1,3-diaxial interaction between two methyl groups introduce into the conformer?

Bromine is a larger atom than chlorine, but the equilibrium constants in Table 3.9 indicate that a chloro substituent has a greater preference for the equatorial position than does a bromo substituent. Suggest an explanation for this fact.

Name the following compounds:

b.

Name the following compounds:

c.