Which of the following are correct?

Options

A. `CH_(3)-O-CH_(2)^(o+)` is more stable than `CH_(3)-CH_(2)^(o+)`
B. `(CH_(3))_(2)CH^(o+)` is less stable than `CH_(3)-CH_(2)-CH_(2)^(o+)`
C. `CH_(2)=CH-CH_(2)^(o+)` is more stable than `CH_(3)-CH_(2)-CH_(2)^(o+)`
D. `CH_(2)=CH^(o+)` is more stable than `CH_(3)-CH_(2)^(o+)`

Answer

To determine which statements regarding the stability of carbocations are correct, we will analyze each statement step-by-step.

### Step-by-Step Solution:

1. **Statement 1: CH3OCH2+ is more stable than CH3CH2+**
- **Analysis**:
- CH3OCH2+ has an oxygen atom that can donate electron density through resonance (−M effect) and inductive effect (+I effect).
- CH3CH2+ does not have such electron-donating groups.
- The resonance stabilization from the oxygen in CH3OCH2+ makes it more stable than CH3CH2+.
- **Conclusion**: This statement is **correct**.

2. **Statement 2: CH3CH2+ is more stable than CH3CH2CH2+**
- **Analysis**:
- CH3CH2+ is a primary carbocation (1°), while CH3CH2CH2+ is a secondary carbocation (2°).
- Secondary carbocations are more stable than primary carbocations due to hyperconjugation and the inductive effect from adjacent alkyl groups.
- **Conclusion**: This statement is **incorrect**.

3. **Statement 3: CH2=CH-CH2+ is more stable than CH3-CH2-CH2+**
- **Analysis**:
- CH2=CH-CH2+ has a double bond that allows for resonance stabilization.
- CH3-CH2-CH2+ is a primary carbocation with no resonance stabilization.
- The resonance in CH2=CH-CH2+ significantly increases its stability compared to the primary carbocation.
- **Conclusion**: This statement is **correct**.

4. **Statement 4: CH2=CH+ is more stable than CH3-CH2+**
- **Analysis**:
- CH2=CH+ is an sp2 hybridized carbocation, while CH3-CH2+ is an sp3 hybridized carbocation.
- The sp2 hybridized carbon has more s-character (33.3%) than the sp3 carbon (25%), making it more electronegative and less stable.
- Therefore, CH2=CH+ is less stable than CH3-CH2+.
- **Conclusion**: This statement is **incorrect**.

### Final Summary:
- **Correct Statements**: 1 and 3
- **Incorrect Statements**: 2 and 4