Question

The IUPAC name of $C{H_3}COCH{(C{H_3})_2}$ is:
A.4-methyl isopropyl ketone
B.3-Methyl-2-butanone
C.Isoroplmethyl ketone
D.2-methyl-3-butanone

Answer 1

Basically, IUPAC nomenclature of organic compound refers to the systematic approach taken for the nomenclature of the organic compound as per the recommendation of the International Union of Pure and Applied chemistry. Moreover, the naming of the compound is done by keeping in mind the rules of IUPAC nomenclature.

Complete step by step answer:
The International Union of Pure and Applied chemistry is basically an international organization designed to address the problems or issues concerning the chemical sciences around the world. Moreover, there are a set of rules given by IUPAC for the systematic nomenclature of the organic compounds. Generally, The IUPAC of organic compounds essentially consists of three parts which are name, prefix, and suffix.
Now as per rules, the first thing is to select the longest carbon chain and in the given compounds the longest chain is of four carbon. Now the chain is numbered and the numbering should begin from the end which is close to the functional group. Here the functional group is the keto group and the numbering will start from the left carbon as the functional group should also have the lowest numbering. Now the substituent methyl group will be at the third carbon.
Therefore, the IUPAC name of the structure is 3-methyl-2-butanone.
Hence, option B is correct.

Note: However, the IUPAC guidelines are not always followed by chemists. This is because some compounds have very long and extremely tedious names. So, these compounds are assigned with trivial names. In trivial nomenclature there is no particular collection of rules for writing the name of the compounds.