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I have studied this reaction for over a year and it makes zero sense. When synthesizing HMX from Bachmann reaction, an important intermediate is DPT. DPT is formed by reaction of nitric and hexamine in acetic acid and acetic anhydride with a 60-65% yield. 63% to be precise according to literature. But, there's a caveat. Everyone who runs this reaction adds them simultaneously. All 3 reactants. I added them in steps like 2 together, 1 in a mixture of 2, all 3 together and in a flow setup as well. Adding them not altogether always decreases the yields. Similarly, decreasing acetic acid and acetic anhydride also reduces yield. One would assume Acetic Acid is the solvent and acetic anhydride the water remover in the reaction but even in a flow setup, if you reduce their ratios, the yields go down. Solvents are not supposed to behave in that manner. IF anyone has any experience with this reaction, can they just explain to me what goes on in it?

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  • $\begingroup$ chempedia.info/info/bachmann_process $\endgroup$
    – Mithoron
    Commented Sep 17, 2022 at 18:50
  • $\begingroup$ This is an overview. I have studied this reaction for over a year. There's nothing in those papers that explains my conundrum which is why I am asking here. $\endgroup$ Commented Sep 17, 2022 at 18:54
  • $\begingroup$ And it would be nice if you linked it yourself. Also, I wouldn't be surprised if it still can provide some insight. $\endgroup$
    – Mithoron
    Commented Sep 17, 2022 at 19:01
  • $\begingroup$ I have read each and every single word in all those papers. There's one mention to the effect I am encountering in the 1953 paper by bachmann himself where he cites private communication on observing the effect I observed. We also got similar yields. 18% mine 20% theirs. I do not have that much insight into flow chemistry and nor do I suspect that they had it so I am asking here. $\endgroup$ Commented Sep 17, 2022 at 19:04
  • $\begingroup$ The illustrations you use show that different conditions for the reaction give worse yields not that flow conditions give worse yields. The actual reaction might be more complex than you think in terms of what is a solvent and what isn't. So are you just asking why you can't further optimise a reaction that has already been optimised? $\endgroup$
    – matt_black
    Commented Sep 20, 2022 at 13:11

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