Reaction Explanation: Acetophenone with CH₃MgBr followed by H₂O

This reaction is a classic example of a nucleophilic addition reaction, specifically the Grignard reaction. Acetophenone, which is a ketone, reacts with methyl magnesium bromide (a Grignard reagent) to form an addition product. Subsequent hydrolysis with water yields a tertiary alcohol.

Step-by-Step Mechanism:

Step 1: Nucleophilic Attack
The Grignard reagent (CH₃MgBr) acts as a nucleophile. The carbon attached to magnesium is electron-rich (due to the C-Mg bond polarity) and attacks the electrophilic carbonyl carbon of acetophenone. $C_{6} H_{5} C (= O) C H_{3} + {CH}^{-} {MgBr}_{+} \to C_{6} H_{5} - \overline{C} (O)^{-} - C H_{3} | C H_{3} MgBr$ This forms a magnesium alkoxide intermediate.

Step 2: Hydrolysis (Reaction with H₂O)
The alkoxide intermediate is protonated by water (acid-base reaction). This step hydrolyzes the O-Mg bond and yields the final tertiary alcohol. $C_{6} H_{5} - C (O)^{-} - C H_{3} | C H_{3} MgBr + H_{2} O \to C_{6} H_{5} - C (O H) - C H_{3} | C H_{3} + Mg (O H) Br$

Final Answer: The product is 1-phenylethanol, a tertiary alcohol. Its structure is:
$C_{6} H_{5} - C (O H) (C H_{3}) (C H_{3})$ This corresponds to the option with the structure: 1-Phenylpropan-2-ol

Related Topics & Formulae

Key Concept: Grignard Reaction
Theory: Grignard reagents (R-MgX) are strong nucleophiles and are highly useful for forming new carbon-carbon bonds. They react with carbonyl compounds (aldehydes, ketones, esters) to yield alcohols after hydrolysis. The type of alcohol produced depends on the carbonyl compound used.

General Formulae:
Reaction with Formaldehyde (HCHO) → Primary Alcohol
Reaction with Aldehyde (RCHO) → Secondary Alcohol
Reaction with Ketone (R₂C=O) → Tertiary Alcohol
Reaction with Ester (RCOOR') → Tertiary Alcohol (after two equivalents)

Important Note: Grignard reagents are very reactive and must be used in anhydrous conditions as they are destroyed by water and other protic solvents.