5-Chloro-2-Methylphenol vs 2-Chloro-5-Methylbenzene?

Why is the compound called 5-Chloro-2-Methylphenol rather than 2-Chloro-5-methylphenol? The occurence of the highest number 5 is exactly the same, so are they both correct? 




The two compound names that you are asking about refer to different compounds. Phenol is numbered as follows:


[![An image showing the numbering of cabron atoms in phenol, with the carbon bearing the hydroxy group numbered 1 and the remaining numbers 2 through 6 assigned clockwise around the ring](https://i.stack.imgur.com/X6pWR.png)](https://i.stack.imgur.com/X6pWR.png)


The structures of 2-chloro-5-methylphenol and 5-chloro-2-methyl phenol are below.


[![The structures of 2-chloro-5-methylphenol and 5-chloro-2-methylphenol emphasizing the numbering of the carbon atoms](https://i.stack.imgur.com/UbVlj.png)](https://i.stack.imgur.com/UbVlj.png)


Perhaps you were confused about the 2,6 or 3,5 isomers? In this case, the chloro- substituent should get the lower locant number because it is alphabetically first.


[![The structures of 2-chloro-6-methylphenol and 3-chloro-5-methylphenol emphasizing the numbering of the carbon atoms](https://i.stack.imgur.com/EeY7w.png)](https://i.stack.imgur.com/EeY7w.png)


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