The reactivity of carbanions follows the order `3^@ gt 2^@ gt 1^@` .

Explanation

To understand the reactivity of carbanions and the order of their reactivity, we need to analyze the stability of carbanions based on their degree (1°, 2°, and 3°). Here's a step-by-step solution:

### Step 1: Define Carbanions
Carbanions are negatively charged carbon species that have a lone pair of electrons. Their reactivity is influenced by their stability, which is determined by the number of alkyl groups attached to the carbon atom bearing the negative charge.

### Step 2: Understand the Degrees of Carbanions
- **1° Carbanion**: A primary carbanion has one alkyl group attached to the carbon atom with the negative charge.
- **2° Carbanion**: A secondary carbanion has two alkyl groups attached to the carbon atom with the negative charge.
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