Organic Chemistry with Biological Applications 3rd Edition – Test Bank

1. Provide the proper IUPAC name for the compound below.

ANSWER:   trans-1-tert-butyl-4-methylcyclohexane or trans-1-(1,1-dimethyl ethyl)-4-methylcyclohexane

POINTS:   1

2. The following is an incorrect name according to IUPAC nomenclature rules. Correct it such that it is a proper IUPAC name.

3-methylhexylcyclopentane

ANSWER:   1-cyclopentyl-3-methylhexane

POINTS:   1

3. Draw and name the seven constitutional isomers for cycloalkane, C₆H₁₂.

ANSWER:  

cyclohexane methylcyclopentane 1,2-dimethylcyclobutane 1,2-dimethylcyclobutane

1,1-dimethylcyclobutane 1,2,3-trimethylcyclopropane 1,1,2-trimethylcyclopropane

POINTS:   1

Instructions: Refer to the structure below to answer the following question(s).

4. Refer to instructions. Which of the labeled groups in the structure are equatorial?

ANSWER:   a and d

POINTS:   1

5. Refer to instructions. Which of the labeled groups is trans to b?

ANSWER:   e

POINTS:   1

6. Refer to instructions. Which groups have a 1,3-diaxial interaction with each other?

ANSWER:   b and c

POINTS:   1

Instructions: For each disubstituted cyclohexane below, draw its ring-flip isomer. Circle the most stable conformation and label the substituent groups as axial or equatorial.

7. Draw and label:

ANSWER:  

conformations are of equal stability

POINTS:   1

8. Draw and label:

ANSWER:  

POINTS:   1

Instructions: Label each pair of compounds below as:

a. identical

b. stereoisomers

c. constitutional isomers

d. identical, but differing in conformation

Where stereoisomers are present, label the isomers as cis and trans.

9. Label:

and

ANSWER:   b

trans   cis

POINTS:   1

10. Label:

and

ANSWER:   a

POINTS:   1

11. For each pair of molecules below, circle the most stable.

and

ANSWER:   and

POINTS:   1

12. Which of the following cycloalkanes has the most ring strain?

  a.  cyclopropane

  b.  cyclobutane

  c.  cyclopentane

  d.  cyclohexane

ANSWER:   a

POINTS:   1

13. Which of the following cycloalkanes would be the most similar to its open chain counterpart?

  a.  cyclodecane

  b.  cyclooctane

  c.  cyclopentane

  d.  cyclopropane

ANSWER:   a

POINTS:   1

14. In which of the following compounds would the carbon−carbon bond angle diverge the greatest from 109°?

  a.  cyclodecane

  b.  cyclooctane

  c.  cyclopentane

  d.  cyclopropane

ANSWER:   d

POINTS:   1

15. In cycloheptane, which of the following factors contributes the least to the stability of the ring conformation?

  a.  torsional strain

  b.  angle strain

  c.  steric strain

  d.  all of these contribute to an approximately equal degree

ANSWER:   b

POINTS:   1

16. Substitution of which of the following groups on a cycloalkane would result in the greatest amount of steric strain?

  a.  bromo

  b.  ethyl

  c.  isopropyl

  d.  hydroxyl

ANSWER:   c

POINTS:   1