Show how you would synthesize octanal from each compound. You may use any necessary reagents. (d) 1-bromoheptane

Verified step by step guidance

1. Step 1: Begin with 1-bromoheptane as your starting material. Recognize that you need to add one carbon to the chain to form octanal.
2. Step 2: Perform a Grignard reaction by treating 1-bromoheptane with magnesium metal in dry ether to form the Grignard reagent, heptylmagnesium bromide.
3. Step 3: React the Grignard reagent with formaldehyde (HCHO) to add one carbon to the chain, forming an alcohol. This step will yield 1-octanol after hydrolysis.
4. Step 4: Oxidize 1-octanol to octanal. Use a mild oxidizing agent such as pyridinium chlorochromate (PCC) to selectively oxidize the primary alcohol to an aldehyde without further oxidation to a carboxylic acid.
5. Step 5: Verify the structure of the final product, octanal, ensuring that the carbon chain is correctly extended and the aldehyde functional group is present at the terminal position.

Key Concepts

Nucleophilic Substitution

Nucleophilic substitution is a fundamental reaction in organic chemistry where a nucleophile attacks an electrophilic carbon atom, replacing a leaving group. In the case of synthesizing octanal from 1-bromoheptane, a nucleophile such as a Grignard reagent or an alkoxide can be used to facilitate the substitution, leading to the formation of an aldehyde.

Carbon Chain Lengthening

Carbon chain lengthening involves increasing the number of carbon atoms in a molecule, which is essential for synthesizing longer-chain aldehydes like octanal. This can be achieved through various methods, such as using alkyl halides in reactions with nucleophiles or through coupling reactions that extend the carbon skeleton.

Aldehyde Formation

Aldehyde formation is a key transformation in organic synthesis, where a carbonyl group is introduced to a carbon chain. In the synthesis of octanal, the final step typically involves oxidizing a primary alcohol or using a suitable reagent to convert an intermediate alcohol into the desired aldehyde, octanal.