REVIEW QUESTIONS FOR UNIT TEST #3 - SUMMER 2003 2. (4 pts) Chlorphedianol, an antitussive compound, has the formula C17H20NOCl. Calculate the degrees of unsaturation for chlorphedianol. Show your calculations for credit.  
 
 
 
 
 
  3. (6 pts) Draw structures corresponding to each IUPAC name below. Either condensed or skeletal structures may be used. a) cis-3,3-dimethyl-4-propyl-1,5-octadiene
 
 
 
 
 
 
 
 

b) E-3-methyl-2-pentene
 
 
 
 
 
 

 4. (4 pts) Rank the substituents below using Cahn-Ingold-Prelog sequence rules by numbering the highest priority substituent 1 and numbering the lowest priority substituent 4. Place the number in the blank below the substituent.   5. You are a manager at SuperTex Chemical Company. A chemist at the company with a degree from tu treats 3,3-dimethylcyclohexene with HCl and is surprised that the major product he isolates has a different carbon skeleton. He is convinced that his alkene must have been assigned the incorrect structure. You need to use your knowledge of organic reaction mechanisms to show him what happened.  

a) (8 pts) Write the complete step-wise mechanism that accounts for the product shown. Show structures of all intermediates and show all electron flow with curvey arrows.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  b) (6 pts) Two other products were formed in smaller amount in this reaction. Draw their structures below.  
 
 
 
  6. (3 pts each) Predict the major organic product(s) in each reaction below. Be sure to indicate stereochemistry when appropriate. a)

b)

c)

d)

e)


7. (6 pts) Give the reagents and starting alkenes to show how the following product can be produced from two different alkenes.

8. (3 pts each) Give the structure of the starting material or of the necessary reagent to complete the following reactions.

a)

 

b)

 
 

9. (4 pts) Carbon-carbon single bonds undergo rotation about the bond with only a small energy barrier, but carbon-carbon double bonds do not undergo rotation under normal conditions. Explain
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

10. (6 pts) Name each of the following types of reactive intermediates of carbon.


 

 11. (4 pts) Identify the least stable and the most stable alkene.  

 
 
 

3. (6 pts) Draw structures corresponding to each IUPAC name below..

a) (2 pts) 2-methyl-3-octyne
 
 
 
 
 
 
 
 

b) (4 pts) (3E, 5Z)-2-methyl-3-bromo-1,3,5-heptatriene
 
 
 
 
 
 
 
 
 
 

 4. (4 pts) Rank the substituents below using Cahn-Ingold-Prelog sequence rules by numbering the highest priority substituent 1 and numbering the lowest priority substituent 4. Place the number in the blank below the substituent.  
 
 
 
  5. (3 pts each) Predict the major organic product(s) in each reaction below. Be sure to indicate stereochemistry when appropriate.  
b) c) d)
  e)
  7. (3 pts each) Give the structure of the starting material or of the necessary reagent to complete the following reactions. a)

b)

 
 
 
  10. Consider the reaction below to answer the following questions.

a) (6 pts)Write the complete step-wise mechanism that accounts for the reaction. Show structures of all intermediates and show all electron flow with arrows.  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  b) There are two other products in this reaction. Draw them below. (4 pts)
 
 
 
 
 
 

11. (4 pts) Explain why the following reaction fails.

12. (5 pts) Carbon-carbon bond forming reactions are important in organic synthesis. Starting with organic starting materials of 4 or fewer carbons, give a method for synthesis of:

(You need to show all reagents and stable intermediate structures.)
 

1.  Draw structures corresponding to each of the following names. Either condensed or line structures may be used.

    1. 4,4,5,5-tetramethyl-2-hexyne
6. (18 pts) Predict the major organic product(s) in each reaction below. Be sure to show stereochemistry when it is relevant.

a)

b)

c)


7.  For each reaction below, indicate the reagent necessary to produce the indicated product. 

b)

8.     (3 pts) Give the starting reactants and reagents necessary to form the following structure:  

11. (6 pts) Ketones are formed by hydration of alkynes. The ketone C below could be prepared by hydration of either alkyne D or alkyne E. However, only one of the transformations (D à C or E à C) would give the desired product selectively.

a) (3 pts) Indicate which reaction would be non-selective and explain why it is not?

 
 
b) (3 pts) Indicate what reaction conditions you would use for the reaction to form C selectively and in high yield.
 
 
  12. (6 pts) Carbon-carbon bond forming reactions are important in organic synthesis. Starting with any organic starting materials of 4 or fewer carbons, show the reactions necessary to complete a synthesis of:

(You need to show all reagents and stable products of each step.)