13. Alcohols and Carbonyl Compounds

Develop syntheses for the following compounds. As starting materials, you may use cyclopentanol, alcohols containing no more than four carbon atoms, and any common reagents and solvents.

(f)

Point out the flaws in the following incorrect Grignard syntheses.

(a)

Draw the organic products you would expect to isolate from the following reactions (after hydrolysis).

(a)

(b)

Metathesis of which of the following sets of alkenes leads to the highest yield of a single alkene?

1. 1-butene and 1-pentene 

2. 2-butene and 3-hexene 

3. 2-butene and 1-pentene

Fill in the boxes with the appropriate reagents:

Two of the methods for converting alkyl halides to carboxylic acids are covered in Sections 20-8B and 20-8C. One is formation of a Grignard reagent followed by addition of carbon dioxide and then dilute acid. The other is substitution by cyanide ion, followed by hydrolysis of the resulting nitrile. For each of the following conversions, decide whether either or both of these methods would work, and explain why. Show the reactions you would use.

(a)

(b)

Using the epoxide shown, addition of an organolithium reagent, when followed by an acid quench, produces only the starting epoxy alcohol. Why? How could the reaction be modified to produce the desired molecule? [Hint: Look back at Section 13.14.]

Predict the product of the reaction

Using the given starting material, any necessary inorganic reagents and catalysts, and any carbon-containing compounds with no more than two carbons, indicate how each of the following compounds can be prepared:

a.

Predict the products of the following reactions.

(d)

(e)

What products are obtained from metathesis of each of the following alkenes?

b.

The Reformatsky reaction is an addition reaction in which an organozinc reagent is used instead of a Grignard reagent to add to the carbonyl group of an aldehyde or a ketone. Because the organozinc reagent is less reactive than a Grignard reagent, a nucleophilic addition to the ester group does not occur.

The organozinc reagent is prepared by treating an α-bromo ester with zinc.

Describe how each of the following compounds can be prepared, using a Reformatsky reaction:

d.

Devise a synthesis for each compound, starting with methylenecyclohexane and any other reagents you need.

f. 1-(phenylmethyl)cyclohexanol