Question

Help explain the process! Starting with acetylene, devise a scheme to prepare 1-chloroheptanol. There is more

than one way to complete this synthesis. It can be completed in as few as three reactions. You can use any alkyl halides as needed as sources of carbon atoms.

Answer 1

The synthesis of 1-chloroheptanol from acetylene involves a Friedel-Crafts acylation to elongate the carbon chain, followed by hydroboration-oxidation to form 1-hexanol, and finally, substitution of the hydroxyl group with a chlorine atom to create 1-chloroheptanol.

Step-by-step explanation:

The synthesis of 1-chloroheptanol from acetylene can be completed in a few steps. First, you need to build the carbon chain to reach heptanol from acetylene, followed by the introduction of functional groups (the hydroxyl and chloro groups). Here is a possible scheme:

1. Perform a Friedel-Crafts acylation on acetylene with an appropriate acid chloride (like hexanoyl chloride) and aluminum chloride (AlCl3) as the catalyst to form 1-hexyne.
2. Carry out a hydroboration-oxidation reaction on 1-hexyne to form 1-hexanol.
3. Lastly, treat 1-hexanol with thionyl chloride (SOCl2) to substitute the hydroxyl group with a chlorine atom, yielding 1-chloroheptanol.

The above reactions make use of principles like carbon chain elongation and functional group transformation. Mastery of organic synthesis techniques including carbon-carbon bond formation and functional group interconversion are critical for devising such a synthesis.