14. Synthetic Techniques

Show how you would synthesize the following compounds. As starting materials, you may use any alcohols containing four or fewer carbon atoms, cyclohexanol, and any necessary solvents and inorganic reagents.

(h)

Beginning with the molecules on the left of each chemical equation, synthesize the molecules shown. While there can be multiple ways of doing each synthesis, the minimum number of steps necessary is indicated over each reaction arrow.

(a)

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

a.

b.

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

b.

Using 1,2-dimethylcyclohexene as your starting material, show how you would synthesize the following compounds. (Once you have shown how to synthesize a compound, you may use it as the starting material in any later parts of this problem.) If a chiral product is shown, assume that it is part of a racemic mixture.

(f)

When doing synthesis, you will often find yourself repeating the same series of steps. To see this in action, synthesize the following aldehydes beginning with an organic molecule containing three carbons or fewer.

(b)

Using hex-1-ene as your starting material, show how you would synthesize the following compounds. (Once you have shown how to synthesize a compound, you may use it as the starting material in any later parts of this problem.)

d. hex-2-yne

e. hexan-2-one

f. hexanal

Supply the reagents necessary to accomplish the following transformation.

Show how you would synthesize the following compounds. As starting materials, you may use any alcohols containing four or fewer carbon atoms, cyclohexanol, and any necessary solvents and inorganic reagents.

(a)

(b)

(c)

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.

(c)

Show how you would synthesize the following compound. As starting materials, you may use any alcohols containing five or fewer carbon atoms and any necessary solvents and inorganic reagents.

Suggest a synthetic scheme, involving a protecting group, to generate the molecule shown starting with the molecule at the left.

(a)

Show how you would use Grignard syntheses to prepare the following alcohol from the indicated starting material and any other necessary reagents.

(e) benzyl alcohol (Ph–CH₂–OH) from bromobenzene (Ph–Br)

Which of the following retrosynthetic disconnections is most appropriate for synthesizing $p_{-}\mathrm{nitroaniline}$ from readily available starting materials?

Using hex-1-ene as your starting material, show how you would synthesize the following compounds. (Once you have shown how to synthesize a compound, you may use it as the starting material in any later parts of this problem.)

g. pentanoic acid

h. pentanal

i. undec-6-yn-5-ol