[wildfyr]

I would suggest trying a higher boiling solvent and doing it at a warmer temperature if there was not much conversion.

Before you do this though, do you feel that all the compounds and solvents you worked with were rigorously dried? Water will ruin this reaction. That means for every 1 g of chloroacetyl chloride, only 0.16 g of water will cause 0 conversion. Water is 0.16 g/100 mL soluble in DCM for instance, so if you had wet DCM, it would ruin the reaction. Wet air will quickly snuff it out as well.

Rigorous denial of water from a reaction is a really critical (and sometimes tough!) skill in organic chemistry.

[Arkcon]

Hi there, sjal: I've merged your two threads, so all the work you've done is together, and you get the best answers.  Sorry to everyone if this makes responses a little bit confusing, but having everything together will make future discussion better.

[sjal]

Could you chlorinate chloroacetic acid? It won't be fun, but you really do need a haloacetyl halide reagent. Halogenating at the acetyl spot on your diarylidenecycloalkanones seems like it would be difficult to do cleanly.

Perhaps make it by using chloroacetic acid and excess PCl5, then distill the product off.

Thank you ... i will try it

[clarkstill]

Please bear in mind that both chloroacetic acid and chloroacetyl chloride are pretty toxic. The chloroacetyl chloride is also a potent lachrymator (i.e. it irritates your eyes).  You need to do a thorough safety assessment before you carry out these reactions, ensuring that you wear appropriate PPE, and ideally carry out all the work in a fume cupboard.

Any wildfyr's point about keeping everything dry is critical. When we say 'dry' we don't just mean that there arent visible drops of water, even a few tens of ppm of water in your solvent can be enough to ruin a reaction. If you don't have access to anhydrous solvents you can use activated molecular sieves to do it in an extremely safe and effective way:

https://pubs.acs.org/doi/full/10.1021/jo101589h?src=recsys

[hypervalent_iodine]

Could you chlorinate chloroacetic acid? It won't be fun, but you really do need a haloacetyl halide reagent. Halogenating at the acetyl spot on your diarylidenecycloalkanones seems like it would be difficult to do cleanly.

Perhaps make it by using chloroacetic acid and excess PCl5, then distill the product off.

This would be my thought too. I know a person in my lab attempted it with thionyl chloride (before he realised we have buckets of the stuff) with little success, but PCl5 seems like a good alternative.

Otherwise, if you don’t have to worry about issues of sea freight to get it, I don’t think the acid chloride is overly expensive. I would buy it in if you can do so easily.

As mentioned, be mindful of your conditions. In my experience, adding the acid chloride to a chilled reaction can be very important as well as making sure it’s dry. Keeping it under inert atmosphere is crucial, and I would recommend a balloon with a wide gage needle for this part. I don’t know how your hood is set up, but I know I would be upset if HCl got into my manifold.

Also good to make sure you are careful with cleaning equipment and wearing / changing gloves. The stuff is deadly toxic, and you do not want to inhale it. I normally quench small amounts (ie. the amounts left over in used glassware, syringes, etc.) of the acid chloride with cold water and rinse with acetone into a waste container inside the hood.

[wildfyr]

This would be my thought too. I know a person in my lab attempted it with thionyl chloride (before he realised we have buckets of the stuff) with little success, but PCl5 seems like a good alternative.

Under most circumstances I would go right for thionyl chloride because typically I'm making either A. a sulfonyl chloride which can handle aqueous workup for the most part or B. nonvolatile acid chloride, from which SOCl₂ can be simple distilled off. In this case, though, chloroacetyl chloride only boils 20°C higher than SOCl₂, and fractional distillation is hard so it makes sense to use a nonvolatile chlorinating agent and isolate with a quick simple distillation. Your lab buddy probably was making plenty of product, just couldnt separate it out.

Anyways, I would bet that water is the heart of OP's problem. It could be in the DCM or the AlCl3, or his acid chloride has mostly hydrolyzed before even getting into the reaction. Its hard to tell how far gone neat acid chloride bottles are because they all reek of HCl anyways, and the 13C looks almost identical.

[hypervalent_iodine]

This would be my thought too. I know a person in my lab attempted it with thionyl chloride (before he realised we have buckets of the stuff) with little success, but PCl5 seems like a good alternative.

Under most circumstances I would go right for thionyl chloride because typically I'm making either A. a sulfonyl chloride which can handle aqueous workup for the most part or B. nonvolatile acid chloride, from which SOCl₂ can be simple distilled off. In this case, though, chloroacetyl chloride only boils 20°C higher than SOCl₂, and fractional distillation is hard so it makes sense to use a nonvolatile chlorinating agent and isolate with a quick simple distillation. Your lab buddy probably was making plenty of product, just couldnt separate it out.

Anyways, I would bet that water is the heart of OP's problem. It could be in the DCM or the AlCl3, or his acid chloride has mostly hydrolyzed before even getting into the reaction. Its hard to tell how far gone neat acid chloride bottles are because they all reek of HCl anyways, and the 13C looks almost identical.

Almost certainly the case, yes. I didn’t ask any more into his issues. I only saw his risk assessment and asked why he was making it when we have a litre in the corrosives cabinet (not his fault - someone removed it from the inventory).

I typically distill chloroacetyl chloride before using it. It is an annoying thing to distil, but just doing that I found boosted my yields by a good 20%. Maybe something to consider in addition to all of the suggestions around removing water.