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Nahum Germanen Godfrey

Replacing the -OH group of a primary alcohol with chlorine

Dinky Dao  Follow
If you heat it should be possible with Lucas reagent but I dont know the yield.
https://en.wikipedia.org/wiki/Lucas%27_reagent

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Aphotic Sapian  Follow
Chlorinating via HCl is possible but it has to compete vs hydrolysis at those high temperatures. I have done a bromination, doing similar using concentrated HBr with Benzene (toluene should work too) and refluxing with a Dean-Stark trap to help remove any water from the mixture and help prevent the hydrolysis.

Another method would be to the Appel reaction https://www.name-reaction.com/appel-reaction . This reaction and is very mild as all you need is carbon tetrachloride and triphenyl phosphine.

These methods are still not as simple as thionyl chloride or even PCl3, which would be my go to, if I had a choice.

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Dare Too  Follow
It might help if we knew the structure of the substrate.

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David Bhattarai  Follow
Everyone is going about this wrong.

Tosylate the alcohol then do an SN2 with a large excess of chloride, i.e. KCl in DMF.

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Aldino Piva  Follow
I would not use HCl to transform a primary alcohol into chloride unless the alcohol is very simple. The problem is that very acidic conditions are needed which could destroy the starting material. Conditions need to be particularly acidic when the alcohol is primary (although this has exceptions, such as when the primary alcohol is a benzylic one with an electron-rich aromatic ring)

Therefore, it is preferable to use SOCl2, which is also not the mildest reagent in the world. There are other alternatives in milder conditions.

The problem is that without knowing what the primary starting alcohol is, it is difficult to calibrate the reagents that this alcohol would withstand without decomposing.

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