Delepine Route to DMMDA-2 from Dillapiole

By Egotrip
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This is the result of much effort ,and the information is as accurate as I can remember. I am sure the colors are correct, and that the times, amounts, etc, are reasonably accurate, I didn't have true scales.

The amounts

  • 25 g dillapiole
  • 240 ml DMSO
  • 18g 93% H2SO4
  • 56g NaBr 99%

The DMSO was frozen solid and removed from icebox. Chilled H2SO4 was added to the DMSO chunk. This heats up a little and liquifies, somewhat, the DMSO. Swirl. Add the NaBr and swirl or stir if you have a good enough (BIG) stirbar. Chopping thru the salt is tough.

With vigorous stirring, the dillapiole is dripped into the DMSO/H2SO4/NaBr mixture, which btw, is now sodium sulfate, and in situ formed HBr.

The rate is a slow one, taking about an hour to get it all in, keeping it cool in a bath. The mixture , before adding dillapiole, is yellow-orange. The addition of dillapiole decolorizes the mess and then begins a slow progression through the pukey-green, to yellowish, to the legendary burgundy. Really, its just a really dark yellow. Maybe with a orangishness. With proper stirring this takes 24 Hrs. It must always stay cool and stay stirring.

Then add 1L ice-water, decant, and the bromo-dillapiole (a heavy orange syrup) doesn't need to be distilled, it is good enough for the next stage. The yield was about 70%

Finkelstein Swap

Measure out an equimolar amount of Sodium iodide, add 5% to that, and suspend your bromo-dillapiole in acetone. Heat it, and as it approaches reflux, carefully add small amounts of the iodide salt to mixture. It darkens, and the reaction is a very visual one, and a very malodourous one, as iodine stinks nicely. Reflux gentle for 30 min (90% yield)!

Delepine reaction

Put the undistilled iodo-dillapiole in 10x amount of alcohol in a 500ml RB flask, heat and begin adding slight molar excess of hexamine until all is in. Refluxing this for 6 hours gave an eventual yield of DMMDA-2 which is quite rewarding. No one should doubt the power of delepine!

The workup:

Add HCl until the ph is 2, and filter off the ass-load of formed ammonium chloride

The red liquid is evaporated until a mass of hard rocklike crystals remained. This is impure DMMDA-2. The crystals CANNOT be cleaned, with ether or any other washes. Freebase and distill to give clear, off colored DMMDA-2.

The yield is 50% from the beginning. SWIM got ~12 g at the end.