Which of the following will form `beta` - amino alcohol with ethylene oxide ?

Options

A. `HOH//H^(o+)`
B. `NH_3`
C. `(CH_3)_2CuLi`
D. `CH_3MgBr`

Answer

To determine which of the given compounds will form a beta-amino alcohol when reacted with ethylene oxide, we can follow these steps:

### Step 1: Understand the Structure of Ethylene Oxide
Ethylene oxide is a three-membered cyclic ether with the formula C2H4O. Its structure can be represented as follows:

```
O
/ \
C C
```

### Step 2: Identify the Reactant
The question mentions reacting ethylene oxide with ammonia (NH3). Ammonia is a simple nitrogen-containing compound that can act as a nucleophile due to the lone pair of electrons on the nitrogen atom.

### Step 3: Mechanism of Reaction
When ammonia reacts with ethylene oxide, the nucleophilic nitrogen attacks the less hindered carbon atom of the epoxide (ethylene oxide). This leads to the opening of the three-membered ring.

1. The nitrogen attacks one of the carbon atoms, leading to the formation of a temporary positive charge on the nitrogen.
2. The ring opens, and the oxygen atom gets a negative charge.
3. The nitrogen can then lose a hydrogen atom to stabilize itself, resulting in the formation of an amino group (NH2) attached to the beta carbon of the original ethylene oxide.

### Step 4: Formation of Beta-Amino Alcohol
After the reaction, the structure can be represented as follows:

```
NH2
|
C - C - OH
|
H
```

Here, the nitrogen is now attached to the beta carbon (the second carbon from the original epoxide), and the hydroxyl group (-OH) is attached to the alpha carbon (the first carbon from the original epoxide). This compound is classified as a beta-amino alcohol.

### Conclusion
Thus, when ethylene oxide reacts with ammonia, it results in the formation of a beta-amino alcohol.