When glycerol is heated with a largher amount of HI or `PI_(3)`, the ptoduct obtained is:

Options

A. Glycerol triiodide
B. Allyl iodide
C. 2-Iodopropane
D. None

Explanation

To solve the question regarding the reaction of glycerol with a large amount of hydrogen iodide (HI) or phosphorus triiodide (PI3), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Structure of Glycerol**:
Glycerol, also known as glycerin, has the chemical formula C3H8O3. Its structure can be represented as:
\[ \text{CH}_2\text{OH} - \text{CHOH} - \text{CH}_2\text{OH} \]

2. **Reaction with HI or PI3**:
When glycerol is heated with excess HI or PI3, it undergoes halogenation. The reaction involves the substitution of hydroxyl (-OH) groups with iodine (I).

3. **Formation of Triiodopropane**:
The first step of the reaction involves the substitution of the three hydroxyl groups in glycerol with iodine atoms, leading to the formation of 1,2,3-triiodopropane:
\[ \text{CH}_2\text{I} - \text{CHI} - \text{CH}_2\text{I} \]
This compound is unstable and can further decompose.

4. **Formation of Aryl Iodide**:
The unstable triiodopropane can undergo elimination reactions, leading to the formation of an aryl iodide (which is a compound containing a double bond):
\[ \text{CH}_2\text{=CH} - \text{CH}_2\text{I} \]

5. **Dehydrohalogenation to Form Propene**:
The aryl iodide can lose an iodine atom to form propene:
\[ \text{CH}_3 - \text{CH} = \text{CH}_2 \]

6. **Final Reaction with HI**:
The propene can then react with another molecule of HI, leading to the formation of 2-iodopropane:
\[ \text{CH}_3 - \text{CH}(\text{I}) - \text{CH}_3 \]

7. **Conclusion**:
Therefore, when glycerol is heated with a large amount of HI or PI3, the final product obtained is 2-iodopropane.

### Final Answer:
The product obtained is **2-iodopropane** (option C).

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