Question

Show how you would synthesize from each compound. You may use any necessary reagents.

(a)$\text{octan - 1 - ol}$

(b)$\text{non - 1 - ene}$

(c)$\text{oct - 1 - yne}$

(d)$\text{1 - bromoheptane}$

(e)$\text{1 - bromohexane}$

(f)$\text{octanoic} \text{acid}$

(g)$\text{ethyl} \text{octanoate}$

Short answer

The structure of is shown below.

$\text{octanal}$

Step-by-step solution

Octanal

The structure of is shown below.

$\text{octanal}$

Synthetic methodology

(a) PCC (pyridinium chlorochromate) oxidizes the primary alcohol ( $\text{octan - 1 - ol}$) to aldehyde ( $\text{octanal}$)

localid="1664867875553" $\text{reaction} \text{a}$

(b) Ozone cleaves the double bonds similar to permanganate to give ketones and aldehydes. $\text{non - 1 - ene}$undergoes ozonolysis to give the products as $\text{octanal}$ and$\text{formaldehyde}$

$\text{reaction} \text{b}$

(c) Hydration of alkyne ( $\text{oct - 1 - yne}$) takes place on treatment with disiamylborane

${\text{Sia}}_{\text{2}}\text{BH}$) in presence of hydrogen peroxide (
${\text{H}}_{\text{2}}{\text{O}}_2$) to give

localid="1664868086642" $\text{reaction} \text{c}$

(d) $\text{1 - bromoheptane}$on treatment with sodium cyanide followed by acid-catalyzed hydration forms $\text{octanal}$ .

$\text{reaction} \text{d}$

(e) $\text{1 - bromohexane}$on treatment with magnesium in ether forms a Grignard product which further reacts with an epoxide (oxirane) and ${\text{H}}_{\text{3}}{\text{O}}^{\text{+}}$gives the product as $\text{octanal}$

$\text{reaction} \text{e}$

(f) $\text{Octanoic} \text{acid}$ undergoes reduction with lithium aluminum hydride${\text{(LiAlH}}_4)$ followed by oxidation with PCC (pyridinium chlorochromate) gives the final product as$\text{octanal}$ .

$\text{reaction} \text{f}$

(g) DIBAL-H reduces $\text{ethyl} \text{octanoate}$ to an aldehyde ($\text{octanal}$ ).

$\text{reaction} \text{g}$