Let's break down the problem step by step: ## **Problem Restatement** You are given an ester and asked to treat it with DIBAH (Diisobutylaluminum hydride) in toluene, followed by aqueous workup (\(\ce{H3O+}\)). **You need to draw the structure of the major organic product(s).** --- ## **Step 1: Identify the Reactant** The given ester is: ``` CH3 | CH3-C-CH2-CH2-O-C(=O)-CH3 ``` Or, more formally: **3-methylbutyl acetate** (an ester). --- ## **Step 2: Understand DIBAH Reaction** - **DIBAH** is a selective reducing agent. - At **low temperature** (usually \(-78^\circ C\)), it reduces **esters** to **aldehydes** (NOT all the way to alcohols, as LiAlH₄ would). - After aqueous workup, the product is an **aldehyde**. --- ## **Step 3: Predict the Major Product** **Ester general structure:** \[ R^1COOR^2 \] DIBAH reduces the ester to an **aldehyde**: \[ R^1COOR^2 \xrightarrow{\text{DIBAH}, \, \text{H}_2\text{O}^+} R^1CHO + R^2OH \] In your structure: - **Acyl part (\(R^1\)) =** CH₃ (from acetate) - **Alkoxy part (\(R^2\)) =** 3-methylbutyl group But the carbonyl carbon becomes the **aldehyde** carbon. ### Let's draw the breakdown: - **Ester:**  - **Product after DIBAH reduction:** - **Aldehyde:** 3-methylbutanal - **Alcohol:** 3-methylbutanol But **DIBAH at low temperature** reduces the ester to the **aldehyde** on the acyl side, not to alcohol. #### So, the product is: ### **3-methylbutanal** **Structure:** ``` CH3 | CH3-C-CH2-CH=O ``` or ``` (CH3)2CHCH2CHO ``` *3-methylbutanal* --- ## **Step 4: Draw the Product** ### **Final Answer** The major organic product is **3-methylbutanal**: ```markdown CH3 | CH3—C—CH2—CHO ``` or as a condensed structure: ```markdown (CH3)2CHCH2CHO ``` **Aldehyde group** is at the end, replacing the ester group after selective reduction by DIBAH. --- ### **Summary Table** | Reagent | Transformation | Product | |-----------------------|-------------------------------------|---------------------| | DIBAH, toluene, H3O+ | Ester → Aldehyde (selective) | 3-methylbutanal | --- **If you need the structure drawn, let me know!**