Propionyl chloride synthesis

[NovicechemistEU]

Propionyl chloride, benzoyl chloride prepared via propionic acid The 1:1 molar ratio of reactants was chosen.


10 mol propionic acid ≈ 747 mL 10 mol benzoyl chloride ≈ 1161 mL (~1:1 molar ratio) in a 2000 mL flask Vertical distillation through a 200 mm column

45-69'C (most collected above 64-69'C) by evacuating a stream of HCl gas from the reaction while finally heating to 190'C to yield 340 g of distillate.
Yield 340 Gr
Note : Really very dangerous synthesis think twice.

 

[NovicechemistEU]

Today I will try another synthesis on a large scale, 5 liters above
1/1 molar ratio 25 mol
Propionic Acid 25 mol **1869 mL
Benzoyl Chloride 25 mol **2903 mL

 

[NovicechemistEU]

I have finished the synthesis but the efficiency is very low, I could not get above 40% maximum, it makes more sense to turn to other ways. Sincerely regards.

 

[William D.]

I have never synthesized with this route, I think FC-reac works more reliable.

 

[Osmosis Vanderwaal]

I was just reading on science madness that a 3:2 ratio (acid:chloride) gave a beter yeild of 82% and there was a link to another paper that suggests 2:1 is even better, but, of course the benzoyl chloride is the expensive reagent, so using more to increase the yield might be counter productive. I'm loooking for an obtainable chlorine source for this reasaction. The pho.pentachloride and trichloride are not available to me, and phosgene is a big no. Thionyl and benzoyl chlroride are tough to get. Are than any options a person can just buy ot easily synthesize?