Carboxylic Acids to Acid Halides

Concept: Concept: Synthesis of Acid Chlorides

Video Transcript

On this page, we’re going to focus on those specific Z-type reactions that turn carboxylic acid into other types of derivatives. We're going to go a little bit more in depth on specific reagents that can transform certain types of derivatives to each other.
The first one is the synthesis of acid chloride. This should be difficult to do because if you remember, acid chloride is the most reactive acyl compound. It’s all the way over here. To get carboxylic acid all the way over here, I’m going to need a strong reagent. That’s exactly what we’re going to use. You guys should have probably seen this reaction already at some point in organic chemistry. But the most common reagent to do this is SOCl2. That’ a very common reagent to add chlorine to all kinds of things, to alcohols, and to carboxylic acids. But there are other reagents we can use. We can also use PCl¬3 or PCl¬5. These reagents are full of chlorines and they’re particularly good at turning a carboxylic acid into an acid chloride. This is helpful for us synthetically because once you have an acid chloride, you can turn that into any other derivative because of how reactive it is and very high yields. Awesome. Let’s move on to the synthesis of amides.