Question

All the following IUPAC names are correct except:
A.$\,1 - \,$chloro $\, - 1 - \,$ethoxypropane
B.$\,1 - \,$amino $\, - 1 - \,$ethoxypropane
C.$\,1 - \,$ethoxypropan $\, - 2 - \,$ol
D.$\,1 - \,$ethoxypropan$\, - 1 - \,$amine

Answer 1

In this question, we have to analyse the structure of each compound and then we have to evaluate whether standard IUPAC naming rules are correctly followed in each of the options so that we can find out the wrong option here. In general, the base component of the name represents the amount of carbon in the parent chain that you have allocated. The name suffix represents the functional group type present on or within the parent chain. Substituents are other groups that are connected to the parent chain.

Complete step by step answer:
Let us analyse each option one by one;
$\,1 - \,$ chloro $\, - 1 - \,$ ethoxypropane
$\,C{H_3}^3 - {H_2}{C^2} - C{H^1}Cl - O - {C_2}{H_5}\,$
Here, the numbering is all correct and hence, the naming is also correct
$\,1 - \,$ amino $\, - 1 - \,$ ethoxypropane
$C{H_3}^3 - C{H_2}^2C{H^1}N{H_2} - O{C_2}{H_5}\,$
Here, as the amino group is the first carbon atom, the parent compound is propan $\, - 1 - \,$ amine. The first carbon atom also has an ethoxy substituent. It can, thus, be written as $\,1 - \,$ ethoxypropan $\, - 1 - \,$ amine. Hence, this naming is incorrect.
$\,1 - \,$ ethoxypropan $\, - 2 - \,$ol
$\,C{H_3}^3 - C{H^2}OH - C{H_2}^1 - O{C_2}{H_5}\,$
Here also naming is as per numbering, as three carbon atoms are there in the parent chain and functionally groups are also numbered correctly. So, this naming is correct.
$\,\,1 - \,$ ethoxypropan $\, - 1 - \,$ amine
$\,\,C{H_3}^3 - C{H_2}^2C{H^1}N{H_2} - O{C_2}{H_5}\,\,$
This structure is similar to that of option B and this is the correct naming of this compound as we saw above.
Hence, for this question option B is the correct answer as it is the only wrong naming here.

Note: As per IUPAC the compound name is written in alphabetical order with the substituents followed by the base name resulting from the number of carbons in the parent chain. Commas are used between numbers, and dashes are used between numbers and letters. Spaces are not used between the names.