IUPAC naming help

[shrister]

Why does OH take priority in numbering over chlorine? In the example I'm looking at on DAT Bootcamp, chlorine is at one end and alcohol is at the other, and chlorine is one bond away from a terminal carbon and alcohol is 2 bonds away from it's terminal carbon. I would assume I would start numbering with the carbon near the chlorine end but the answer is to start numbering chain closest to alcohol.

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[pilotdentist]

One of the first Ochem videos for "Chad's Videos" outlines the functional group priority list. Bootcamp is correct, -OH is above halides in priority...

 

[shrister]

One of the first Ochem videos for "Chad's Videos" outlines the functional group priority list. Bootcamp is correct, -OH is above halides in priority...

So it's prioritized by which substituent is more electronegative?

 

[shrister]

No, it's because alcohols are an actual functional group and rank higher than halogens on the "which gets the suffix name?" table. Here is a reliable table that I used which covers just about all of the functional groups required for the test.

Note that ethers and halogens rank below alkanes. That in short means that neither will ever be given the suffix name of the molecule. Priorities like this are difficult to remember, so I would suggest inventing a mnemonic for them. Have fun and hope this helped!

This definitely helped. Thanks! As for what I said about electronegativity, chad says that if you're stuck between which suffix to use, higher electronegativity helps. In the example I gave alcohol gets priority because it's the only functional group.