In `S_(N^(1))` reaction an optically active substrates mainly gives

Options

A. Retention in configuration
B. Inversion in configuration
C. Racemic product
D. No products

Answer

To solve the question regarding the outcome of an SN1 reaction involving optically active substrates, we can break down the steps as follows:

### Step-by-Step Solution:

1. **Understanding SN1 Reaction**:
- The SN1 (Substitution Nucleophilic Unimolecular) reaction involves two main steps: the formation of a carbocation intermediate and the nucleophilic attack.
- The rate-determining step is the formation of the carbocation, which is influenced by the stability of the carbocation.

2. **Formation of Carbocation**:
- When an optically active substrate undergoes an SN1 reaction, it first loses its leaving group (e.g., a halide ion), resulting in the formation of a planar carbocation.
- This carbocation is sp² hybridized and can be attacked by the nucleophile from either side, leading to different configurations.

3. **Nucleophilic Attack**:
- Since the carbocation is planar, the nucleophile can attack from either the front (retaining the original configuration) or the back (inverting the configuration).
- This results in two possible outcomes: retention of configuration (same as the original) and inversion of configuration (opposite to the original).

4. **Probability of Each Outcome**:
- The nucleophile has an equal probability (50%) of attacking from either side of the planar carbocation.
- Therefore, there is a 50% chance of obtaining the original configuration (retention) and a 50% chance of obtaining the inverted configuration.

5. **Resulting Product**:
- The combination of both outcomes leads to a racemic mixture, which contains equal amounts of both enantiomers (the retained and inverted forms).
- Thus, the product formed from an optically active substrate in an SN1 reaction is a racemic mixture.

### Conclusion:
The correct answer to the question is that in an SN1 reaction involving optically active substrates, the product formed is a **racemic product**.

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