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The preparation of AET

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starlight:
One of Glennon's papers suggests that AET shows stimulus generlization to MDMA in experimental animals. It was considered a worthwhile pursuit to determine whether this held true for a human subject.

1-(3-indolyl)-2-nitrobutene
85ml acetic acid, 8ml acetic anhydride, 5g ammonium acetate, 14.4g (100mmol) indole-3-carboxaldehyde and 20ml (220mmol) nitropropane were put in a 250ml erlenmeyer with condenser attached. The reaction contents were stirred and kept at 85-90°C for three hours (using an oil bath)

The heat source was removed, the flask was cooled, and 100ml of water was added. The flask was then left overnight, after which the whole lot was vacuum filtered. The solids so obtained were recrystallized twice from ~100ml EtOH to give 8.9g 1-(3-indolyl)-2-nitrobutene as shiny orange crystals (40% yield based on the indole-3-carboxaldehyde used).

1-(3-indolyl)-2-nitrobutane
8.5 g (40 mmol) 1-(3-indolyl)-2-nitrobutene was added during 30 minutes to a solution of 1.9 g (50 mmol, 1,25 mol eq.) sodium borohydride in 25 ml water and 50 ml IPA.

The reaction ran a lot slower than with a phenyl-2-nitrobutene or phenyl-2-nitropropene. It was assumed that this was due to the low solubility of the substrate in IPA/H20 (it is also pretty insoluble in toluene - a Red-Al reduction was considered but the solubility in toluene at room temp is close to zero - THF cosolvent is called for here).

After all the substrate was added, the solution was stirred for another 2 hours, by which time only a slight yellow color remained to the solution (starting material is orange).

At this point 50% acetic acid was added dropwise until the effervescence subsided. NaCl was poured in until no more dissolved and stirred vigorously for five minutes. The reaction was then vacuum filtered to remove the insolubles.

The filtrate separated into an upper yellow alcoholic layer, and a lower aqeous layer. The aqeous layer was discarded. The IPA layer was used in the next reaction. It was assumed from the color change that this stage of the reaction had worked nicely (looked like any other nitrobutene/nitropropene reduction to the nitrobutane/nitropropane).

The solution of 1-(3-indolyl)-2-nitrobutane in IPA was left overnight before conducting the next reaction.

1-(3-indolyl)-2-aminobutane
40ml of IPA was added to the IPA layer from the previous reaction. 0.6g of 10% Pd/C was added to the IPA layer and then the mixture was stirred.

In another beaker 3.6 ml of water was mixed with 13.2 g of 85% KOH. 10.8 g of 85% HCOOH was dripped in to the KOH/H2O.

The potassium formate/H2O was poured into the Nitrobutane/IPA flask and the mixture was heated to 75C while stirring. Evolution of hydrogen was noted around 40C. Throughout the course of this CTH (2.5 hours), the effervescence kept stopping and would restart on the addition of more catalyst. About 3ml of GAA were added during the course of the reaction to keep it a nice consistency. In all about 2g of 10% Pd/C were added (in the end addition of more catalyst did not cause any further hydrogen evolution and the reaction was considered to be over.

The reaction mixture was vacuum filtered and the filtercake was rinsed with a little IPA. The final filtrate was light yellow in color.

The filtrate was saturated with table salt and filtered. The lower aqeous layer/NaCL slurry was discarded and the IPA stripped at atmospheric pressure.

The result was about 9g of Orange/Brown tar which was insoluble in 5% HCl.

Something went wrong in this last reduction. Would you expect 1-(3-indolyl)-2-nitrobutanes/nitropropanes to reduce with CTH normally?

Why did the catalyst stop working and need supplementing? - is this catalyst poisoning? CTH has worked properly on phenyl-2-nitropropanes for the same research lab.

Do trypatmines have a habit of forming tar when compared to phenethylamines?

Oh, and lastly does anyone here have first hand experience of the activity of the desired product?

Rhodium:
Do trypatmines have a habit of forming tar when compared to phenethylamines?

Yes, most definitely. Purification through flash chromatography (or short-path high-vac distillation) very often has to be performed to get something which can be crystallized as a salt.

Oh, and lastly does anyone here have first hand experience of the activity of the desired product?

Yes, such descriptions can be read in None (http://www.erowid.org/library/books_online/tihkal/tihkal11.shtml)

starlight:
Yes, most definitely. Purification through flash chromatography (or short-path high-vac distillation)

Somehow I don't think that would have helped in this case. If you have a ball of brown tar that won't even partially dissolve in HCl I think the game is pretty much over really.

Thanks for the TiKAL Ref. I had looked at those, but was wondering if anybody here had first-hand experience.

Another attempt will be made.

Lilienthal:
Maybe you have formylated your tryptamine?

starlight:
Unless somebody here has had good success with CTH of similar compounds, then maybe another reduction system should be tried.

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