The electrophile involved in the Reimer-Tiemann reaction is

Options

A. `CHCl_(3)`
B. `:CH_(2)`
C. `:C Cl_(2)`
D. `CO_(2)`

Answer

To determine the electrophile involved in the Reimer-Tiemann reaction, we can follow these steps:

### Step 1: Understand the Reimer-Tiemann Reaction
The Reimer-Tiemann reaction is an electrophilic substitution reaction that involves phenol and chloroform (CHCl3) in the presence of a strong base, typically sodium hydroxide (NaOH) or potassium hydroxide (KOH). The primary product of this reaction is salicylaldehyde.

**Hint:** Recall that electrophilic substitution reactions involve the replacement of a hydrogen atom in an aromatic compound with an electrophile.

### Step 2: Identify the Reactants
In the Reimer-Tiemann reaction, the reactants are phenol (C6H5OH) and chloroform (CHCl3). The strong base (NaOH or KOH) is crucial for the reaction to proceed.

**Hint:** Identify the components of the reaction and their roles. The strong base is essential for generating the electrophile.

### Step 3: Formation of the Electrophile
The electrophile is generated from chloroform when it reacts with the hydroxide ion (OH-). The hydroxide ion abstracts a proton from CHCl3, leading to the formation of a carbanion intermediate.

**Hint:** Remember that bases can abstract protons, leading to the formation of reactive intermediates.

### Step 4: Identify the Intermediate
The carbanion formed from the reaction of CHCl3 and OH- is a dichlorocarbene (CCl2). This species is a highly reactive electrophile that will attack the aromatic ring of phenol.

**Hint:** Look for the species that has a positive charge or is electron-deficient, which indicates it is an electrophile.

### Step 5: Conclusion
After the formation of dichlorocarbene (CCl2), it acts as the electrophile in the Reimer-Tiemann reaction, leading to the substitution on the phenolic compound and ultimately forming salicylaldehyde.

**Hint:** Confirm that the electrophile is indeed the species that will react with the aromatic compound to form the final product.

### Final Answer
The electrophile involved in the Reimer-Tiemann reaction is **CCl2 (dichlorocarbene)**.