21. Aldehydes and Ketones: Nucleophilic Addition

Give the nitrile and organometallic reagent you would use to make the following ketones. There are two possible answers for both.

(a)

Give the nitrile and organometallic reagent you would use to make the following ketones. There are two possible answers for both.

(b)

Draw a mechanism for the acidic hydrolysis of the magnesium salt shown below to acetophenone.

What is the best set of reagents to use for the synthesis?

What is the best set of reagents to use for the synthesis?

2.

What carbonyl compound and what phosphonium ylide are needed to synthesize the following compounds?

b.

Show how you would accomplish the following synthetic conversions efficiently and in good yield. You may use any necessary additional reagents and solvents.

(a)

Show how you would accomplish the following synthetic conversions efficiently and in good yield. You may use any necessary additional reagents and solvents.

(d)

Show how you would accomplish the following syntheses efficiently and in good yield. You may use any necessary reagents.

(b)

Show how Wittig reactions might be used to synthesize the following compounds. In each case, start with an alkyl halide and a ketone or an aldehyde.

(a) Ph–CH=C(CH₃)₂

(b) Ph–C(CH₃)=CH₂

Show how Wittig reactions might be used to synthesize the following compounds. In each case, start with an alkyl halide and a ketone or an aldehyde.

(c) Ph–CH=CH–CH=CH–Ph

(d)

Predict the major products of the following reactions.

(h)

(a) Outline the syntheses indicated in Solved Problem 18-2, beginning with aldehydes and alkyl halides.

(b) Both of these syntheses of 1-phenylbuta-1,3-diene form the central double bond. Show how you would synthesize this target molecule by forming the terminal double bond.

Using cyclohexanone as the starting material, describe how each of the following compounds can be synthesized:

f.

Show how you would synthesize octanal from each compound. You may use any necessary reagents.

(f) octanoic acid