Which of the following compound has maximum "C-C" single bond length ?

Options

A. `CH_(2)CHC CH`
B. HC C C CH
C. `CH_(3)CHCH_(2)`
D. `CH_(2)CHCHCH_(2)`

Explanation

To determine which of the given compounds has the maximum "C-C" single bond length, we will analyze the structures of each compound and consider the effects of conjugation and hybridization on bond lengths.

### Step-by-Step Solution:

1. **Identify the Compounds**:
The compounds given are:
- A: CH2=CH-C≡CH
- B: CH≡C-CH2-CH
- C: CH3-CH2-CH=CH2
- D: CH2=CH-CH=CH2

2. **Draw the Structures**:
- For Compound A (CH2=CH-C≡CH): This has a double bond between the first two carbons and a triple bond between the last two carbons.
- For Compound B (CH≡C-CH2-CH): This has a triple bond between the first two carbons.
- For Compound C (CH3-CH2-CH=CH2): This has a double bond between the last two carbons.
- For Compound D (CH2=CH-CH=CH2): This has two double bonds.

3. **Analyze Conjugation**:
- In Compound A, the presence of a double bond and a triple bond creates conjugation, which leads to partial double bond character in the C-C single bond.
- In Compound B, the triple bond also contributes to conjugation, resulting in a shorter C-C bond length.
- In Compound C, there is a double bond, but it is not in conjugation with other multiple bonds, so the C-C bond is likely longer than in A and B.
- In Compound D, the presence of two double bonds creates conjugation, which again leads to shorter C-C bond lengths.

4. **Determine the Maximum C-C Bond Length**:
- Since compounds A, B, and D all exhibit conjugation, their C-C single bond lengths will be shorter due to the partial double bond character.
- Compound C does not have conjugation affecting the C-C bond, so it will have the longest C-C single bond length.

5. **Conclusion**:
The compound with the maximum "C-C" single bond length is **C: CH3-CH2-CH=CH2**.