Organic Chemistry III

Professor Carl C. Wamser

Chem 336 - Spring Term

Exam 1

1.  (15 points)  Write complete names for each of the following:

a) 

b) 

c) 

d) 

e) 


2.  (15 points)  Write complete structures for the following:

a) the best resonance form for the enolate anion of ethyl acetoacetate (acetoacetic ester)

b)  the aldol condensation product from 3-pentanone

c)  the Claisen condensation product from ethyl hexanoate (after hydrolysis and decarboxylation)

d)  all possible enols of butanone

e)  p-cyanophenyl cyclopentanecarboxylate


3.  (15 points)  Complete the following reactions by adding the missing part, either the necessary reagents and conditions or the final major product.

a) 

b) 

c) 

d) 

e) 


4.  (15 points)  Complete the following reactions by adding the missing part, either the necessary reagents and conditions or the final major product.

a) 

b) 

c) 

d) 

e) 


5.  (15 points)  Write a complete mechanism for the acid-catalyzed reaction below.
Show all steps and all resonance forms for any intermediates involved.
You may use H+ and  -H+ to show proton transfer steps.


6.  (10 points)  Complete the following synthetic scheme by filling in the boxes as appropriate.


7.  (15 points)  Aldol products may be dehydrated either by excess heating during the base-catalyzed reaction or by acid catalysis, as shown below.

Write a complete mechanism for the dehydration shown above.  In particular, your mechanism must show that conversion to the enol is required before the dehydration can take place.

Explain why the enol form allows for a more favorable mechanism.