Which of the following is the correct IUPAC name?
Which of the following is the correct IUPAC name?
The correct option is B 3−Ethyl−4,4−dimethylheptane
IUPAC nomenclature of the above compound
Some important rules for naming alkaneas:
1. Identify the longest carbons chain. This chain is called the parent chain.
2. Number the carbons of the parent chain which gives the substituent lowest number.
3. Write the name of the compound with substituents in alphabetical order followed by base name (derived from parent chain).
4. If one substituent appears more than one time. Use di, tri, tetra etc to show the number of times substituent occurs. Bis, tris like prefix are used only when di, tri like words are already present in the name of substituent.
Option (A)
3−Ethyl−4,4−dimethylheptane
Structure based on this IUPAC name would be as given below :-
So, for naming the compound as per IUPAC, given rules should be followed :
1. Identify the longest carbons chain. This chain is called the parent chain.
2. Number the carbons of the parent chain which gives the substituent lowest number.
3. Write the name of the compound with substituents in alphabetical order followed by base name (derived from parent chain).
4. If one substituent appears more than one time. Use di, tri, tetra etc to show the number of times substituent occurs. Bis, tris like prefix are used only when di, tri like words are already present in the name of substituent.
And we can see that all the rules for naming, as per IUPAC convention are being followed there in option (A).
Hence, option (A) is correct.
Option B:
4,4−Dimethyl−3−ethylheptane
Structure based on this IUPAC name would be as given below :-
For 4,4−Dimethyl−3−ethylheptane substituents are not written in alphabetical order. Hence, the IUPAC name is incorrect.
Option (C)
5−Ethyl−4,4−dimethylheptane
Structure based on this IUPAC name would be as given below :-
For 5−Ethyl−4,4−dimethylheptane numbering of carbons of the parent chain is wrong, because substituent ethyl did not get the lowest number possible.
Hence, option (C) is incorrect.
Option (D)
4,4−Bis(methyl)−3−ethylheptane
For 4,4−Bis(methyl)−3−ethylheptane, proper word have not been used for the two times appearance of the methyl group. i.e, “di” should be used in place of “bis”. Also, the alphabetical order is wrong in the option because prefixes do not count for alphabetizing purposes
Hence, option (D) is incorrect.
3−Ethyl−4,4−dimethylheptane
IUPAC nomenclature of the above compound
Some important rules for naming alkaneas:
1. Identify the longest carbons chain. This chain is called the parent chain.
2. Number the carbons of the parent chain which gives the substituent lowest number.
3. Write the name of the compound with substituents in alphabetical order followed by base name (derived from parent chain).
4. If one substituent appears more than one time. Use di, tri, tetra etc to show the number of times substituent occurs. Bis, tris like prefix are used only when di, tri like words are already present in the name of substituent.
Option (A)
3−Ethyl−4,4−dimethylheptane
Structure based on this IUPAC name would be as given below :-
So, for naming the compound as per IUPAC, given rules should be followed :
1. Identify the longest carbons chain. This chain is called the parent chain.
2. Number the carbons of the parent chain which gives the substituent lowest number.
3. Write the name of the compound with substituents in alphabetical order followed by base name (derived from parent chain).
4. If one substituent appears more than one time. Use di, tri, tetra etc to show the number of times substituent occurs. Bis, tris like prefix are used only when di, tri like words are already present in the name of substituent.
And we can see that all the rules for naming, as per IUPAC convention are being followed there in option (A).
Hence, option (A) is correct.
Option B:
4,4−Dimethyl−3−ethylheptane
Structure based on this IUPAC name would be as given below :-
For 4,4−Dimethyl−3−ethylheptane substituents are not written in alphabetical order. Hence, the IUPAC name is incorrect.
Option (C)
5−Ethyl−4,4−dimethylheptane
Structure based on this IUPAC name would be as given below :-
For 5−Ethyl−4,4−dimethylheptane numbering of carbons of the parent chain is wrong, because substituent ethyl did not get the lowest number possible.
Hence, option (C) is incorrect.
Option (D)
4,4−Bis(methyl)−3−ethylheptane
For 4,4−Bis(methyl)−3−ethylheptane, proper word have not been used for the two times appearance of the methyl group. i.e, “di” should be used in place of “bis”. Also, the alphabetical order is wrong in the option because prefixes do not count for alphabetizing purposes
Hence, option (D) is incorrect.
