Question

What is the correct IUPAC name of the given compound?
               

(a) 4-methoxy-2-nitrobenzaldehyde
(b) 4-formyl-3-nitroanisole
(c) 4-methoxy-6-nitrobenzaldehyde
(d) 2-formyl-5-methoxynitrobenzene

Answer 1

Hint: While writing the IUPAC name of any compound, we will first identify the primary group and the substituents attached to it and we will start numbering from that carbon from which the attached substituent is nearest and while writing the name that name of substituent will be written first which comes first in the alphabetic order along with the carbon number respectively. Now write the name of the compound.

Complete Solution :
The IUPAC stands for the International Union of Pure and Applied Chemistry and it is the method that is used for the naming of the organic or inorganic compounds and the compounds are known by their IUPAC naming all over.
- The given compound belongs to the category of aldehydes as it consists of -CHO group which is the primary group attached to the benzene ring and nitro and the ethoxy groups i.e. $N{O}_2$ and $OC{H}_3$ are present as the substituents attached to the benzene ring.
- In the IUPAC naming of the aldehyde, the suffix aldehyde is added at the end of the IUPAC name and for the attached substituents prefix nitro and ethoxy is added at the starting of the carbon chain along with the carbon number to which they are attached.
- Since, there are two substituents attached i.e. the nitro and ethoxy groups , then we will write that name of the substituent first which comes first according to the alphabetic order i.e. in the above we can see that the m of methoxy group comes first then the n of the nitro group, so methoxy group will be written first and after that the nitro group.
- So, now criteria for naming the compound is as:
Carbon no.( prefix of first substituent)-carbon no.(prefix of second substituent)-compound name along with the suffix of primary group.
- Hence, the IUPAC name of the given compound is as:

So, the correct answer is “Option A”.

Note: Always remember that while writing the substituent name , the name of that substituent will be written first which comes first according to the alphabetical order thereafter followed by the next substituent and the compound name.