IUPAC name of `CH_2 = C (CH_3) - CH OH - CH_2 CHO` is…..........

Explanation

To determine the IUPAC name of the compound `CH2 = C(CH3) - CH(OH) - CH2CHO`, we will follow these steps:

### Step 1: Identify the longest carbon chain
The first step in naming an organic compound is to identify the longest continuous carbon chain that includes the functional groups. In this case, the longest chain consists of 5 carbon atoms.

### Step 2: Number the carbon chain
We need to number the carbon chain in such a way that the functional groups get the lowest possible numbers. The functional groups present here are an alcohol (-OH) and an aldehyde (-CHO). The aldehyde is more oxidized than the alcohol, so we will number the chain from the end nearest to the aldehyde group.

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