UPDATE 2023: This thread now also includes some experiments that were conducted, added after that theoretical ideas. But the first analyze of the Spectra had an error: DMT-N-Oxide was mistaken with the DMSO-Signal. That gave a wrong amount of signals which would have indicated a polymerization. Sadly the corrected spectrum does not give any strong signs of polymerization and therefore the title was also changed back, to account for a still more theoretical discussion about polymers
Part 1: Theoretical considerations
So over the years there was a huge
talk about DMT Polymerization. When heating pure white Spice on a hot plate, most of it vaporizes, but still there is some orange residue, which will not vaporize above 180 °C. This residue seems to be dissolve slower in Acetone than regular DMT. Also I've seen some Spice crashing out very fast at Room Temperature, while another portion just came out in the Freezer. Ok ... yes this is normal for Re-X, but I mean it felt like these were different batches of Stuff.
So either its just a sort of combustion with charred products left behind, or indeed DMT may form bigger structures that dont vaporize readily.
A possible solution to distinct between combustion products and polymers would be vaporization in N2-Atmosphere obviously.
But how could any possible Multimer of DMT look like? Amines would be the most reactive part of the molecule obviously, but when looking into other examples in literature it may be something different:
1. The enzymatic polymerization of Psilocybin uses that 5-position and 2-position. Now as this is an enzymatic reaction, there is no direct translation, but if Nature is doing stuff, then it mostly means something - or in other words, it indicates that both positions may be most promising if also using heat. (
source)
2. Fischer-Indole Synthesis is using Hydrazine precursors and electrophile fragments to build tryptamines. While performing such a reaction it may be possible to get fragments with higher mass which evolve by excessive nucleophile attack of that 2-position Carbon. I think this also indicates that this 2-position may be indeed quite reactive. (
source)
3. Another paper even specificially talks about this pathway of general indole polymerization, so I guess that this may really be the most meaningfull way of also polymerizing (by accident) DMT. (
source)
In principle that tryptamine skeletton could act as either nucleophile or electrophile, with electron-donating substitutens even increasing nucleophile character:
But this way only Dimers could be formed. To get up to multimers with more than 2x of DMT mass like Benzyme saw
in MS this could then only happen by 2,3-addition. The 3-position would also be a good nucleophile, due to forming a tertiary carbo cation in acidic environments. In this picture these 2,3-polymers are shown. (Yet for substituted indols like DMT, this 3-position would be super hindered). (
source)
Any easy way to verify that would be to retrieve a sample with possible polymers ...
Loveall wrote:I think Jees and I are also seeing evidence that polymerization can occur over time in basic water at high pH (or high ionic strength) and high DMT concentration.
Perhaps all extractions have some degree of DMT polymerization while basing? Maybe it can be minimized by managing these factors (?).
... and extract just the DMT by pulling with a low amount of Room Temperature Naphtha for 5 min and then throw the residual stuff in NMR.
If indeed this is the way of DMT-Polymerization then the
Signals at 1H 7,1 ppm (2-Position) --> should be (nearly) gone
or at least not fit anymore to stochiometrySignals at 13C 122 ppm (2-Position) --> 127 ppm - ok ... this will be super hard to see/distinguish/verify ...
Directly jump to the experiments about DMT-Polymers HERE on Page 2. Part 2: Experiments to get some insights into the DMT-Polymer structure
Sadly there was an error in the discussion of both NMR. It is important to have a signal which can be normalized to the spectrum in a way that the spectrum depicts exactly 1 molecule. This way it is possible to measure a decrease of certain protons and therefore a successive polymerization of molecules. Sadly I was pretty dumb and mistook the solvent signal (DMSO) for being the N-Oxide. Now it's corrected and means we have much less N-Oxide and therefore also much less reacted DMT. The new text reflects the proper results.I tried to induce DMT-Polymer formation and then analyze with NMR. 2 possible ways were examined: base-catalyzed polymerization and radical-induced polymerization. I have no idea if any of these will indeed induce a polymerization, but that's why I did those experiments obviously ... It does not reflect how DMT may polymerize inside of a cooking pot while extracting, but I thought it could be a more direct patchway and make it easier to find any clues of it's structure.
NMR spectroscopy results in a spectrum which can be used to idenfity certain structural features of a molecule depending on the protons attached to it. Every proton will give a signal in 1H-NMR and the X-axis position of those is depending on the chemical environment. Different environments will cause signals at different X-axis positions, which is labelled at [ppm] as unit. Now when looking at the respective unsaturated DMT signals (the one which are believed to may cause polymerization) a decrease of these signals will show that the total amount of those protons was decreased per average molecule. Now the signal which has reduced the most indicates a place where a reaction may have taken place to the highest amount, ultimately leading to the possibly most reactive site of the molecule regarding a possible polymerization reaction.
Comment: Sadly I'm not using the correct nomenclature to numberize the atoms - my NMR Analysis Prediction is determining the numbering and I have no idea how to change it, so I'm just going with that. To make things worse this numbering seems to change from time to time, but well then you can play Sherlok Holmes trying to follow these numbers.1.) Base-catalyzed Polymerization
Idea:DMT is used without solvent to maximize concentration and therefore polymerization chance. The sample is heated above melting point to speed up reaction of course, but also to give DMT enough mobility to undergo a reaction. As a base Triethylamin (Et3N) is added, which is a much stronger base than DMT and might accelerate the formation of nucleophiles that could be the initial step of forming a polymer, as well as for potential propagation reactions.
Procedure:- Heat DMT for 10 days at 70 °C + 1 wt-% Triethylamin added every 3 days
Resulting dark oil was extracted 2x with boiling Heptane to keep only what is insoluble in Alkanes to ensure not picking up un-polymerized stuff.
Resulting Polymer: 5 mg (from 100 mg)
N-Oxide: (3,13 ppm)We can see some N-Oxide, which is in a ratio of roughly 1,80 : 4,18 = 43 %. But that is not the N-Oxide in the whole DMT, but the one that was left when extracting. To calculate inside the whole batch:
100 mg DMT heated
5 mg DMT-Oil remained which is 43 % N-Oxide
= 2,5 mg N-Oxide =
2,5 % N-OxideSo actually a pretty low amount of N-Oxide considering that it was heated for so many days. Still in that
old experiment when heating for 2 h at 100 °C there was no N-Oxide. So it seems if you totally exaggerate with heating you indeed get quite some N-Oxide, even when there is no light present. Still those are just traces and probably not the reason why the rest did not dissolve in Heptane.
Aromatic Signals: (6,98 - 7,50 ppm)
Sadly they look exactly like before. No signal reduction. That would indicate none of these indolic sp2-carbons underwent any reaction and therefore probably also no polymerization to be seen here ...
Indolic NH: (10,84 ppm)
Here we have a signal that is only at 68 % strength of what it should be based on former measurements. Still that proton is somewhat acidic / loosely bound and therefore might exchange with Deuterium in the solvent. That again means that the magnitude of integral of those acidic protons are something not to be taken too seriously when comparing the absolute values. Still there is a definite decrease to be observed. That would mean this N has reacted in some kind of way, probably around 1/3 of them inside of the whole sample that was left over after Heptane boiling. But as there is no reaction observable within the same magnitude of any other carbons of the aromatic signals, there was probably no coupling with any of these. Only viable option would be coupling both N with each other, which would not happen in a base-catalyzed reaction. It can be simply seen that we have 3 different types of this signal:
NH a) = 10,66 ppm (0,05 = 11 %)
NH b) = 10,84 ppm (0,27 = 61 %) -
this is unreacted DMT (at least pos. 5 & 6)NH c) = 10,96 ppm (0,12 = 28 %)
A signal which is probably the same, but shifted a little left or right indicates a very similar structure with some minor differences within close proximity (1-3 bonds remote of the corresponding Proton). In NMR closely bound substituents will have an impact on the chemical shift and shape of peaks. If that peak is shifted, it could indicate that there was a reaction at position C5 (only option within max. 3 bonds distance to NH6) taking place, that shifted the signal either left (higher ppm) or right (lower ppm). In general it is possible to explain the chemical shift based on chemical environment like this in an easy way:
Higher ppm: Proton has a low electron density, with high electron density neighbour atoms and polar bond
Example = Acetic Acid H-OOC-R
Lower ppm: Proton does not have reduced electron density, with no increased electron density neighbour atoms and not polar bond
Example = Methan H-CH3
So a shift that could have taken place, when considering options for polymerization would be as follows:
Higher ppm could be induced by reaction of C5 with N6 of another molecule.
Lower ppm could be induced by reaction of C5 with any other sp2-carbon of another molecule.
10,84 ppm is DMT without any reaction at C5 or N6
What is missing now in total to Integral = 0,87 has reacted with N6 and is therefore invisible.
Sadly we dont have a sign for any C5 reaction and so there is also not too much as an insight from here. Still a reaction of N6 with other sp2-Carbons would be possible as also discussed in the big thread of DMT-Polymerization by Loveall, see
post of Benzyme.
Benzyme wrote:The paper I linked proposes (and it has been shown before), that dimerization linkages actually occur from N1->C3.
This isn't particularly surprising, as autooxidation also affects that C3 position of indole.
Impurities:We can see some impurities in the aliphatic range at 2,07 ppm and lower. But these are nothing that would be displayed by DMT or a DMT polymer that would exist based on the theoretical thoughts above, so also no further hint.
Summary:Sadly no sign of polymerization. Indeed the signal of the NH at Position 6 seems reduced. But there is no hint what kind of coupling could have happened, as there is no corresponding C-atom which also has a decreased signal.
The first evaluation was performed wrong and assumed that another signal was the N-Oxide. Therefore the overall amount of signals was reduced much more and this lead to a heavy decrease of those aromatic sp2 R-CH=R bonds. The NMR based on this assumption is still seen
here. Maybe someone with more training would see if there is not maybe still some hint of a reaction. This probably wrong assumption lead to the polymer structure shown
here, but this one is probably not true or at least not a consequence of the newly-discussed NMR-result.
2.) Radically-induced Polymerization
Idea:DMT is used without solvent to maximize concentration and therefore polymerization chance. The sample is heated above melting point to speed up reaction of course, but also to give DMT enough mobility to undergo a reaction. As an Initiator the classic thermally-activatable AIBN was used. This one needs also 70 °C for decomposition and will create radicals.
Procedure:Heat DMT for 1 night at 70 °C + 1 wt-% Azobis(isobutyronitril) (AIBN)
Resulting dark oil was extracted 2x with boiling Heptane to keep only what is insoluble in Alkanes to ensure not picking up un-polymerized stuff.
Resulting Polymer: 4 mg (from 50 mg)
N-Oxide: (3.20 ppm)We see much less N-Oxide, only like 5 %. But as this is only the sample with the unreacted DMT removed by Heptan the calculation of the whole content is:
50 mg DMT heated
4 mg DMT-Oil remained which is 5 % N-Oxide
= 0,2 mg N-Oxide =
0,4 % N-OxideThat is actually much less than in the base-catalyzed setup. Of course this one was heated much shorter, but AIBN is a radical initiator and thus I would have expect to produce quite a bunch of N-Oxide. So formation is much lower than in the first experiment and even negligible in total. A foolproof way to create N-Oxide with Radicals is H2O2, which will go to 100 % conversion within just 1 night. But here you create Oxygen Radicals, which are maybe not so prone to evolve if you start with AIBN in concentrated DMT.
Aromatic Signals: (6,95 - 7,53 ppm)
As before basically no reduction in the total signal count (5 -> 4,74). This drop could also be within the uncertainty of NMR-measurement with these type of sp2-Carbons. So no hint of polymerization as above ...
Indolic NH: (10,79 ppm)
This time only 1 signal, but the reduction is also probably not within the error range as it is - 28 % (100 % should be ~ 0,87). So probably something happened here again and it is nearly at the same magnitude like for the reaction above. But also here we dont have any signs what could be the corresponding coupling.
Impurities:Nothing to be seen except water and the solvent (DMSO). Looks like some pretty pure DMT, which is in this rare case not really what I was hoping for
The first evaluation was performed wrong and assumed that another signal was the N-Oxide. Therefore the overall amount of signals was reduced much more and this lead to a heavy decrease of those aromatic sp2 R-CH=R bonds. The NMR based on this assumption is still seen
here. As these results were kind of similar for both reactions, a reactivity pattern was also assumed based on how strongly the signal of each proton decreased and shown
here. As also with the polymer structure this is both not a consequence of the newly analyzed and corrected spectrum, so probably outdated.
Summary:So after correcting the formerly probably wrong evaluation, there is no sign anymore of DMT-coupling. It was a pretty much fitting theory that was put up in the first time and without contradictions, but as now there is no real proof of this anymore, it's better to drop what can't be proven
Whatever is left from these reactions, it is impossible to dissolve it anymore in Heptane at any temperature. Therefore I strongly believe this is some kind of heavily altered Tryptamine. Still, it just shows up as regular DMT once again
Not sure which other experiment could be done. But it's just weird to me that no matter which
Polymer is analyzed it always shows up as just DMT. Benzyme got some
perfect proofs of polymerization with the Mass Spec, but even this experiment right here could not give any answers HOW these molecules might be attached to each other, of course probably just because the conditions did not create any polymers in the first place. Still these conditions were thought to be really effective at it, which makes me wonder how to strongly force that polymerization alltogether.