[Tom_Boomer]

Hey everybody, I am doing my Bachelor thesis on an organic synthesis. I was wondering if I were to add thionyl chloride (SOCl2) and dimethylformamide (together they form the Vilsmeier-Haack reagent) to 4-hydroxyphenylacetic acid, I would observe a polymerization reaction as the Vilsmeier-Haack reagent would convert the carboxylic acid into an acid chloride which could then be attacked by the remaining alcohol groups on the other molecules of 4-hydroxyphenylacetic acid.

The entire reaction I am trying to conduct involves the addition of triethylamine and a dimethyl formamide HCl salt to finalize the amidation reaction, however, adding the DMA.HCl has had no effect on the reaction mixture even though I would expect an exothermic reaction.

Thanks for the help in advance!

[swankybracelet]

In the case of 4-hydroxyphenylacetic acid, the Vilsmeier-Haack reagent (formed by the reaction of SOCl2 and DMF) would indeed convert the carboxylic acid group into an acid chloride. This acid chloride could potentially react with the remaining alcohol groups on other molecules of 4-hydroxyphenylacetic acid, leading to the formation of ester linkages and potentially polymerization.

Regarding the addition of triethylamine and DMA.HCl to finalize the amidation reaction, it's important to note that DMA.HCl (dimethylformamide hydrochloride) is typically used as a reagent to generate the amine species required for the amidation reaction. It is possible that DMA.HCl is not playing a significant role in the exothermic reaction you expected. Other factors, such as reaction conditions and concentrations, might also influence the outcome.

[Tom_Boomer]

Thank you so much for your answer! I found some literature on the topic which showed that alkaline conditions are necessary in order for the phenol to be reactive enough (it first would have to be transformed into the phenoxide ion). Would the added triethylamine be a strong enough base to deprotonate the phenol or could the phenol already react without the help of the TEA? The reason I'm asking this is because I did a IR-spec (with accompanying database) which showed short chain PET-polymers (a structure that is relatively equal to the structure you would get through the acid chloride polymerization). Also I'm really sorry but I think I made a mistake in my original post, the DMA.HCl refers to the dimethylamine HCl salt, not the dimethylformamide HCl salt. Very sorry for the confusion!

I was wondering that, if I would not want any polymerizations to occur, should make use of an alcohol protecting group?

Thanks for your time again!

[Borek]

Tom - the answer you got was from a spammer, no idea if it was worth anything, no idea if you are part of the setup.

One thing I am sure about is that all unnecessary links and all spamming accounts will be deleted, sooner or later.

[Tom_Boomer]

Dear Borek, I am not quite sure what you mean by "part of the setup". This was my first time using this forum so I'm very sorry if I did anything wrong, I did not mean to offend anyone. Would it be okay if I reposted the question (while phrasing it better too) to make sure no spammer reacts to it?

[Borek]

Dear Borek, I am not quite sure what you mean by "part of the setup". This was my first time using this forum so I'm very sorry if I did anything wrong, I did not mean to offend anyone.

Unfortunately quite often someone comes here and asks a highly specific question (which technically is perfectly OK and in accordance with forum rules), which is then answered by another newcomer.  99% of the time that means the same person asking and replying, just to post a spam link at some point. I am not saying that's what you are doing, just that such threads always raise a suspicion.

Would it be okay if I reposted the question (while phrasing it better too) to make sure no spammer reacts to it?

No way to do that. No matter how you ask these days just putting the question into ChatGPT will produce something looking "answerlike", you just never know whether it makes technical sense. Spammers don't care, they just need a reasonably looking post.

Sad state of the internet and internet forums, not your fault

[rolnor]

Hey everybody, I am doing my Bachelor thesis on an organic synthesis. I was wondering if I were to add thionyl chloride (SOCl2) and dimethylformamide (together they form the Vilsmeier-Haack reagent) to 4-hydroxyphenylacetic acid, I would observe a polymerization reaction as the Vilsmeier-Haack reagent would convert the carboxylic acid into an acid chloride which could then be attacked by the remaining alcohol groups on the other molecules of 4-hydroxyphenylacetic acid.

The entire reaction I am trying to conduct involves the addition of triethylamine and a dimethyl formamide HCl salt to finalize the amidation reaction, however, adding the DMA.HCl has had no effect on the reaction mixture even though I would expect an exothermic reaction.

Thanks for the help in advance!

I think the 4-hydroxygroup will react with the Vilsmeyer reagent as well, that is not good? And I am not sure; DMF HCl salt sounds strange? Do you mean Vilsmeyer reagent?