An alkyl halide (A), on reaction with magnesium in dry ether followed by treatment with ethanol gave 2-methylbutane. Write all the possible structures of A.

Explanation

To determine the possible structures of the alkyl halide (A) that can yield 2-methylbutane upon reaction with magnesium in dry ether followed by treatment with ethanol, we can follow these steps:

### Step 1: Understand the Reaction
The alkyl halide (A) reacts with magnesium to form a Grignard reagent (RMgX). The Grignard reagent then reacts with ethanol, leading to the formation of an alkane. In this case, the final product is 2-methylbutane.

### Step 2: Analyze the Structure of 2-Methylbutane
2-Methylbutane has the following structure:
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