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

Using the given starting material, any necessary inorganic reagents, and any carbon-containing compounds with no more than two carbons, indicate how the following syntheses could be carried out:

a.

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)

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.

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)

a. Propose a mechanism for the following reaction.

2 (CH₃)₂C=CH–CH₃ + cat. H⁺ → 2,3,4,4-tetramethylhex-2-ene

b. Show the first three steps (as far as the tetramer) in the BF₃–catalyzed polymerization of propylene to form polypropylene.

Develop syntheses for the following compounds, using acetylene and compounds containing no more than four carbon atoms as your organic starting materials.

(a) 3-methylnon-4-yn-3-ol (“3-ol” means there is an OH group on C3.)

Develop syntheses for the following compounds, using acetylene and compounds containing no more than four carbon atoms as your organic starting materials.

(b) cis-1-ethyl-2-methylcyclopropane

Propose mechanisms to explain the opposite regiochemistry observed in the following two reactions.