An alkene on reductive ozonolysis gives two products A and B . When these products are treated with conc. KOH one of these products gives an alcohol and an acid salt. Here the alkene can be

Options

A. But -2- ene
B. Pent -2- ene
C. Isobutene
D. cyclo hexene

Answer

To solve the problem, we need to analyze the alkene that undergoes reductive ozonolysis and produces two products, A and B. One of these products, when treated with concentrated KOH, yields an alcohol and an acid salt.

### Step-by-Step Solution:

1. **Understanding Reductive Ozonolysis**:
- Reductive ozonolysis involves the cleavage of the carbon-carbon double bond in alkenes to form carbonyl compounds (aldehydes or ketones) using ozone followed by a reducing agent like dimethyl sulfide (Me2S).
- The general reaction can be represented as:
\[ R_1CH=CHR_2 \xrightarrow{O_3} R_1C(=O)R_2C(=O)R_3 \]

2. **Identifying Products A and B**:
- After ozonolysis, the products A and B will be carbonyl compounds. Depending on the structure of the alkene, these can be either aldehydes or ketones.
- The key is to determine which of these products can undergo a Cannizzaro reaction when treated with concentrated KOH.

3. **Cannizzaro Reaction**:
- The Cannizzaro reaction occurs with aldehydes that do not have alpha hydrogens. In this reaction, one molecule of the aldehyde is oxidized to a carboxylic acid while another is reduced to an alcohol.
- Therefore, we need to identify which product (A or B) does not have alpha hydrogens.

4. **Analyzing the Given Options**:
- **Option A: But-2-ene**
- Ozonolysis gives two molecules of acetaldehyde (CH3CHO). Both products have alpha hydrogens.
- **Option B: Pent-2-ene**
- Ozonolysis gives two products: propanal (CH3CH2CHO) and acetaldehyde (CH3CHO). Both products have alpha hydrogens.
- **Option C: Isobutene**
- Ozonolysis gives acetone (CH3COCH3) and formaldehyde (HCHO). Formaldehyde has no alpha hydrogens, making it a candidate for the Cannizzaro reaction.
- **Option D: Cyclohexene**
- Ozonolysis gives two molecules of cyclohexanone (C6H10O), which have alpha hydrogens.

5. **Conclusion**:
- The only option that fits the criteria of producing a product without alpha hydrogens is **Option C: Isobutene**. When treated with concentrated KOH, formaldehyde undergoes the Cannizzaro reaction to yield methanol and formic acid.

### Final Answer:
The alkene can be **Isobutene**.