In IUPAC system of naming of organic compounds. Which of the following functional group has more preference than other ( in a poly functional compound)

Options

A. `-OH`
B. `-CHO`
C. `-CO-`
D. `-CONH_(2)`

Answer

To determine the functional group that has more preference than others in a polyfunctional compound according to the IUPAC system of naming, we need to follow the priority order of functional groups. Here’s a step-by-step solution:

### Step 1: Identify the Functional Groups
First, we need to identify the functional groups present in the polyfunctional compound. Common functional groups include:
- Carboxylic acids (-COOH)
- Sulphonic acids (-SO3H)
- Acid derivatives (like esters, amides)
- Aldehydes (-CHO)
- Ketones (R-CO-R')
- Alcohols (-OH)

### Step 2: Understand the Priority Order
According to IUPAC nomenclature, functional groups have a specific priority order when naming polyfunctional compounds. The priority order is as follows:
1. Carboxylic acids
2. Sulphonic acids
3. Acid derivatives (like esters and amides)
4. Aldehydes
5. Ketones
6. Alcohols

### Step 3: Determine the Highest Priority Functional Group
From the priority order, we can see that the carboxylic acid group has the highest preference. Therefore, if a compound contains a carboxylic acid along with other functional groups, the carboxylic acid will take precedence in naming the compound.

### Step 4: Conclusion
In a polyfunctional compound, the functional group with the highest preference is the **carboxylic acid group**.