Naming this organic compound [duplicate]








**This question already has an answer here**:
 
 




[IUPAC Naming of CH3C(p-ClC6H4)2CH(Br)CH3](/questions/81144/iupac-naming-of-ch3cp-clc6h42chbrch3)

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Closed 4 years ago.



What’s the name of the following compound?


$$\ce{CH3C(p-ClC6H4)2CH(Br)CH3}$$


My teacher said that she strongly thinks( with another teacher) that it should be **3-bromo-2,2-bis-(4-chlorophenyl)butane**, though many other books and other students (similar to me) stated that it should be **2-bromo-3,3-bis-(4-chlorophenyl)butane**.


She asked us try to find it out. Any organic chemistry experts out there?




I think your teacher is correct, numbering of carbons is done acording to the lowest locant rule.
[![numbering](https://i.stack.imgur.com/7SeYG.png)](https://i.stack.imgur.com/7SeYG.png)


The red numbering gives you : 2, **3**, 3


The green numbering gives you : 2, **2**, 3


We see that the first point of difference between the two numberings occurs at second number, so the green numbering is preferred.
Consequently, the correct name should be : **3-Bromo-2,2-bis(4-chlorophenyl)butane**


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