Chem 240 - Spring 1999

Fourth Exam, April 21, 1999

1. (8) Give correct IUPAC names for the following compounds. Be sure to include E-Z designations where appropriate

a.
b.

 

2. (8) Draw structures which correspond to the following IUPAC names.

a. 3-ethyl-1-pentene b. 3-methyl-1-butyne

 

 

 

 

 

3. (16) a. Circle the strongest base. Underline the weakest base.

b. Circle the structure of the compound which reacts fastest in an electrophilic aromatic substitution reaction. Underline the structure of the compound which reacts slowest in an electrophilic aromatic substitution reaction.

c. Circle the structure of the aromatic cation. Underline the structure of the aromatic heterocycle.

d. Circle the structure of the C5H10 isomer which is most stable. Underline the structure of the C5H10 isomer which is least stable.

4 (24) Write appropriate formulas for the products of the following reactions. Be clear about stereochemistry where required.

a.

 

b.

 

c.

6.7c

 

d.

 

e.

f.

5. (18) For each of the following reactions, place the structure of the needed reactant in the box. If isomeric products are formed in any step, assume that they can be separated.

 

a.

 

b.

 

 

c.

 

 

 

6. (10) Show how you could carry out the following synthetic scheme by listing the necessary reagents in the proper sequence.

7. (8) What is the product of each of the following reactions

.

a.

b.

 

 

8. (8) Explain the reasons for the differences in the product of the two reactions in question 7. Your explanation must include equations for the key steps which lead to the different results.