In the given reaction `CH_3-C-=Choverset(HOBr)rarr[X]`
[X] will be

Options

A. `CH_3-overset(O)overset(||)C-CH_2Br`
B. `CH_3-overset(O)overset(||)C-CBr_3`
C. `CH_3-overset(O)overset(||)C-CHBr_2`
D. `CH_3-overset(O)overset(||)C-CHBr`

Answer

To solve the problem regarding the reaction of `CH3-C≡C-CH` with `HOBr`, we need to analyze the reaction step by step.

### Step 1: Identify the Reactants
The reactant is `CH3-C≡C-CH`, which is an alkyne (specifically, a terminal alkyne). The presence of a triple bond indicates that the compound is electron-rich due to the presence of pi electrons.

**Hint:** Recognize that alkynes can act as nucleophiles because of their electron-rich nature.

### Step 2: Understand the Electrophile
`HOBr` consists of a hydroxyl group (OH) and a bromine atom (Br). In this case, the bromine atom can act as an electrophile because it can accept electrons.

**Hint:** Identify the parts of `HOBr` that can participate in the reaction. The Br atom is the electrophile.

### Step 3: Nucleophilic Attack
The pi electrons from the triple bond of the alkyne will attack the electrophilic bromine atom in `HOBr`. This forms a new bond between the alkyne and the bromine, leading to the formation of a bromonium ion intermediate.

**Hint:** Remember that nucleophiles attack electrophiles to form new bonds.

### Step 4: Rearrangement
After the formation of the bromonium ion, the structure can undergo rearrangement. The double bond can shift, and the OH group can attach to the more substituted carbon due to stability reasons. This process leads to the formation of an enol.

**Hint:** Consider the stability of the resulting enol; more substituted alkenes are generally more stable.

### Step 5: Final Product Formation
The final product `[X]` after rearrangement will be a brominated compound where the OH group is attached to the carbon that was originally part of the triple bond, resulting in a product that can be represented as a ketone after tautomerization.

**Hint:** Tautomerization can convert an enol into a ketone or aldehyde, depending on the structure.

### Conclusion
The final product `[X]` will be a brominated enol or ketone, depending on the specific structure of the starting alkyne and the reaction conditions.

### Final Answer
The product `[X]` will be a brominated compound derived from the reaction of `CH3-C≡C-CH` with `HOBr`.