Exam 17: Carbonyl Alpha-Substitution and Condensation Reactions

Instructions: Each of the following compounds in the following question(s)can be prepared by a mixed aldol condensation reaction. a)Give the structures of the aldehyde and/or ketone precursors for each aldol condensation product and formulate the reaction. b)Give the structure of the intermediate aldol product. -Refer to instructions.Use the following compound:

Instructions: Give the major organic product(s)of each reaction or sequences of reactions for the following question(s).Show all relevant stereochemistry. Refer to instructions.

How many different aldols (b-hydroxyaldehydes),including constitutional isomers and stereoisomers,are formed upon treatment of butanal with base?

Instructions: Give the major organic product(s)of each reaction or sequences of reactions for the following question(s).Show all relevant stereochemistry. -Give major product(s):

Instructions: Draw the structures of the precursors to the Michael reaction products shown in the question(s)below.Label the Michael donor and the Michael acceptor in each case and formulate the reaction. -Draw and label:

Instructions: Draw the structure of the product you would expect to obtain by Claisen condensation of the esters shown in the question(s)below.If an ester does not undergo Claisen condensation,explain why it does not. -Draw and explain:

Instructions: Consider the structures below to answer the following question(s). -Refer to instructions.Underline the acidic hydrogen atoms in each of the molecules.

Identify the intermediate imine that results from the following reaction.

How would you prepare 5-methyl-2-hexanone using an acetoacetic ester synthesis?

Which of the following would form an enol on treatment with an acid?

Identify products a and b.

Instructions: Consider the reaction sequence below to answer the following question(s). -Refer to instructions.The starting material A in this reaction sequence is called a(n)_____.

Instructions: Consider the reaction sequence below to answer the following question(s). - Refer to instructions.Conversion of B into C involves hydrolysis of the ester followed by decarboxylation.On the structures provided below,show the electron flow for the decarboxylation step.

Instructions: Each of the following compounds in the following question(s)can be prepared by a mixed aldol condensation reaction. a)Give the structures of the aldehyde and/or ketone precursors for each aldol condensation product and formulate the reaction. b)Give the structure of the intermediate aldol product. -Refer to instructions.Use the following compound:

Which of the following does not possess an enol form? Explain your choice.

Instructions: Draw the structure of the product you would expect to obtain by Claisen condensation of the esters shown in the question(s)below.If an ester does not undergo Claisen condensation,explain why it does not. -Draw and explain:

Instructions: Draw the structures of the precursors to the Michael reaction products shown in the question(s)below.Label the Michael donor and the Michael acceptor in each case and formulate the reaction. -Draw and label:

How would you prepare the following compound using an alkylation reaction?

Instructions: Consider the reaction below to answer the following question(s). -Refer to instructions.Write the complete stepwise mechanism for the reaction above.Show all intermediate structures and all electron flow with arrows.

How would you prepare 3-phenylpropanoic acid using a malonic ester synthesis?