I require a small amount of triflic acid, and while other research groups do not have any, I did locate some trflic anhydride. Does anyone have a published protocol for obtaining the anhydrous acid from the anhydride?

I tried to distill under a slow stream of nitrogen about 10 mL of triflic anhydride (yellow/brown solution) with about 5 mL of DI H2O. I got a clear colorless fraction coming off with B.P. 66 C, and afterwards a second fraction with a slightly lower boiling point. The boiling point of the free acid is 162C, the anhydride is 82 C, and there is a monohydrate of the free acid with a melting point of 34 C, but I couldn't find the boiling point. 

I did not find an entry in Perrin & Armarego Purification 3rd edition, or in my Fieser and Fieser. 

I'll run 19F NMR on the 2 distilled fractions I got, but as the BP was so low, I expect not to get the free acid.

  • $\begingroup$ ...google ....trifluoromethanesulfonic acid CF3SO3H $\endgroup$ – Karl Nov 15 '16 at 22:07
  • $\begingroup$ If I had done that and found the answer, I wouldnt be asking here, would I? $\endgroup$ – Efram Goldberg Nov 20 '16 at 4:46
  • $\begingroup$ My comment was merely to identify the substance. Anyway, what did you expect to get from that distillation procedure? As your supervisor, I would be frowning at you, badly. $\endgroup$ – Karl Nov 20 '16 at 10:05
  • $\begingroup$ Normally anyhydrides will hydrolyze to the free acids in the presence of water. That's basic undergrad organic chemistry. If you dont know that you really shouldnt be attempting to comment. $\endgroup$ – Efram Goldberg Nov 21 '16 at 15:48
  • $\begingroup$ Well, "basic undergrad chemistry" seems to have failed you. Hydrolysation of anhydrides if often slow, from my own undergrad and graduate OC experience. And how do you expect to isolate the highest boiling substance in that hydrolysation by distillation? At ambient pressure no less, and nitrogen stream? That's simply bad laboratory practice, sorry. Not talking of a second fraction that comes at lower temperature. $\endgroup$ – Karl Nov 21 '16 at 19:03

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