That’s awesome! I love seeing parent & child teams in chemistry! 
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Sure thing… ive done the reaction several times but have not yet been able to correlate efficiencies with analytics/identification. Think we got a new process to achieve maximum efficiencies but we will have to wait on that. I normally just dissolve distillate in aa and reflux for 6 + hours. The aa is so heavy that the reflux barely condenses above the joint to the reflux condensor. I have no idea the efficiencies but given that im using distillate and not pure thc, as well as just dissolving instead of using some catalytic agent, i imagine that the reaction is fairly impure.
If you were to use a solvent i mght suggest heptane since its boiling point is much nearer to aa than shorter chains. I also am not sure how much benefit could come from the sulfuric catalyst.
Still radically changes the effects of bioassay. Eating it was no different than eating distillate with the exception that it was slightly more sedative. Smoking it is amazing however. I dont understand how, but if its properly made its the smoothest thing out there. A noobie could take a gram dab of it and not cough, and its incorporation in other products will smooth them out extremely. It also hits quick after a inhalation, but then seems to become less effective until 45 minutes in, where the psychoactivity seems to climb… an hour in and youll ask yourself why you feel like youre getting higher, than you realize its the acetate. Great for muscle relaxation and sedation ime.
I always distill the product post reaction/neutralization. After the reaction i distill off the aa, then neutralize with supersaturated sodium bicarbonate solution in distilled h2o. Last reaction i got a 137% yield on the synthesis, but that dropped to around 74% post distillation, although there was a decent amount of a heavier fraction that i have not seen before.
I actually believe in machoulams original isolation of thc he acetylated his product, then distilled it, that deacetylated it before binding to a urea matrix. The molecule is heavier but the boiling point is lower, oddly enough. Distills around 165 at sub 100 micron depths
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Fascinating @Psilisophical ! Thank you for the insight on the distillation post reaction! From the bioassay report, it sounds like you are making a mixture of THC and other cannabinoids along with their acetylated counterparts. I imagine CBD-diacetate could be among them, since you are not using acid, and the acetic intermediate is mostly just conjugate base… although you are freeing H+ ions, that conjugate base is strong, making the acid weak.
As we discussed previously, I think adding acid catalyst (p-tosic, perhaps, with its 140 °C b.p. at 20 mmHg) would be beneficial to your end of higher THC-acetate yield (although it sounds like the mixture is rather nice). Though it may result in some isomerization, it would drive the acetylation reaction to higher yield, and Δ8-THC-O-acetate would be smooth indeed. Time (or enthalpy calculations) will tell if the acid catalysis of the acetylation rxn uses the acid before, after, or during isomerization, but bioassay is the real metric for any drug.
Just be aware that tosic is usually sold and used as monohydrate. Tbh, 98% sulfuric acid is a gas in about 2% water, and thereby more dangerous to use with the acetic anhydride. Stay safe, my friend!
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I have never actually made THC acetate, or even consumed it to be honest. Is it stable in high temperatures such as dabbing, or does it decomp to THC and some byproduct?
Thank you for your reply. I always learn something new when you post. I am going to try and make thc acetate without a catalyst and then later compare results with catalyst. Do you think that having an inert atmosphere like nitrogen would help limit side reactions in the reflux stage (140C for 3 to 6 hours)? In Cannabis Alchemy Gold does not specify if purpose of a nitrogen atmosphere is for safety or for the reaction as well.
It is both for safety and reactive purposes. Acetic anhydride is a pyrophoric reagent, I believe, and it hygroscopically reacts with water in air. That reaction is exothermic and spontaneous, and especially at elevated temperatures, it can hit the flash point and self-ignite. Definitely do it in a sealed dry atmosphere!
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Bretherick’s Handbook of Reactive Chemical Hazards Seventh Edition Volume 1
- Acetic anhydride
[108-24-7]
C4H6O3
(MCA SD-15, 1962); HCS 1980, 101
The principal reaction hazard attached to use of acetic anhydride is the possibility of rapid and exothermic acid-catalysed hydrolysis unless the conditions prevailing (temperature, agitation, order of mixing, proportion of water) are such as to promote smooth and progressive hydrolysis with adequate heat removal. The examples below illustrate these factors.
Acetic acid, Water
MCA Case History No. 1865
Erroneous addition of aqueous acetic acid into a tank of the anhydride caused violent exothermic hydrolysis of the latter. See Water, below
Ammonium nitrate, Hexamethylenetetraminium acetate, Nitric acid See Nitric acid: Acetic anhydride, etc.
Barium peroxide See Barium peroxide: Acetic anhydride
Boric acid 1. Lerner, L. M., Chem. Eng. News, 1973, 51(34), 42 2. Experiments in Organic Chemistry, 281, Fieser, L. F., Boston, Heath, 1955 Attempted preparation of acetyl borate by slowly heating a stirred mixture of the anhydride and solid acid led to an eruptive explosion at 60C [1]. The republished procedure being used [2] omitted the reference to a violent reaction mentioned in the German original. Modifying the procedure by adding portions of boric acid to the hot stirred anhydride should give a smoother reaction.
Bromohydroxybiphenyl, Pyridine, Water Nolan, 1983, Case History 36
Bromohydroxybiphenyl was O-acetylated with excess acetic anhydride in pyridine. The excess anhydride was to be hydrolysed by addition of water, but this was done without proper control using a hosepipe. The hydrolysis reaction ran away, causing boiling and evaporation of the reactor contents. See Acetic acid, above; Water, below
N-tert-Butylphthalamic acid, Tetrafluoroboric acid Boyd, G. V. et al., J. Chem. Soc., Perkin Trans. 1, 1978, 1346 Interaction to give N-tert-butylphthalisoimidium tetrafluoroborate was very violent, possibly because of exothermic hydrolysis of the anhydride by the 40% aqueous tetrafluoroboric acid. See Tetrafluoroboric acid, below
Chromic acid 1. Dawkins, A. E., Chem. & Ind., 1956, 196 2. Baker, W., Chem. & Ind., 1956, 280 Addition of acetic anhydride to a solution of chromium trioxide in water caused violent boiling [1], due to the acid-catalysed exothermic hydrolysis of the anhydride [2].
Chromium trioxide See Chromium trioxide: Acetic anhydride
1,3-Diphenyltriazene See 1,3-Diphenyltriazene: Acetic anhydride
MRH 2.38/84
Ethanol, Sodium hydrogen sulfate Staudinger, H., Angew. Chem., 1922, 35, 657 Accidental presence of the acid salt vigorously catalysed a large scale preparation of ethyl acetate, causing violent boiling and emission of vapour which became ignited and exploded. See other CATALYTIC IMPURITY INCIDENTS
Glycerol, Phosphoryl chloride Bellis, M. P., Hexagon Alpha Chi Sigma (Indianapolis), 1949, 40(10), 40 Violent acylation occurs in catalytic presence of phosphoryl chloride, because the high viscosity of the mixture in absence of solvent prevents mixing and dissipation of the high heat of reaction.
Water 1. Leigh, W. R. D. et al., Chem. & Ind., 1962, 778 2. Benson, G., Chem. Eng. News, 1947, 25, 3458 Accidental slow addition of water to a mixture of the anhydride and acetic acid (85:15) led to a violent, large scale explosion. This was simulated closely in the laboratory, again in the absence of mineral-acid catalyst [1]. If unmoderated, the rate of acid-catalysed hydrolysis of (water insoluble) acetic anhydride can accelerate to explosive boiling [2]. Essentially the same accident, fortunately with no injuries or fatalities this time, was repeated in 1990.
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I 2nd that! Thank you! 
Hello everyone and I want to start by thanking everyone that helped so far and an extra thank you to @Psilisophical for putting up with my constant questions.
Here is what I did to replicate and modify what Cannabis Alchemy’s procedure. Excuse my lack of scientific formality.
Procedure:
1.) Transferred 10.04g of thc distillate into a 250ml rbf.
2.) Using a glass transfer pipette transferred 51g of acetic anhydride(AA) into previously mentioned 250ml rbf.
3.) Placed stir bar into rbf and used stirring to fully dissolve distillate into AA
4.) Transferred the rbf into nitrogen atmosphere. Sealed and flooded the environment with nitrogen before continuing.
5.) Refluxed for 3 hours (refluxed on the neck not the condenser)
6.) Distilled off the majority of the AA under vacuum in nitrogen atmosphere.
7.) Using ethanol as a solvent, transferred product from 250ml rbf to 50ml two neck rbf for distillation. Ethanol was used to transfer and wash to avoid transfer loss.
8.) Vacuum distillation:
Performed a fractional distillation with THC distillation equipment. First fraction was collected from 0-150C. Second fraction was collected from 150-210C
Side note:
Ethanol and AA contact was limited to less than 30 minutes and immediately distilled to prevent ethanol reaction with AA.
Discussion:
I understand that any THC that didn’t get converted into THC actate would also be collected in the second fraction. Is there any way to quantify THC aceatae? I don’t know many people making this so standards would be hard to come by. I would like to know what % thc vs %thc acetate so I can determine if I need to reflux for longer.
I would like to discuss the reaction between AA and wet ethanol to determine if this is a good way to remove any excess and toxic AA. If moisture in the air spontaneously reacts to form acetic acid then 5% or more water in ethanol should convert the entire excess AA into acetic acid. Or at least that’s my thinking. I researched if ethanol would react with the AA because of the OH group and found that it is limited as long as it’s kept at room temp or below. The reaction between AA and ethanol is ethyl ethanoate which is a toxic solvent but has a boiling point lower than THC acetate under vacuum. I would love if @Photon_noir could help with this.
(source: preparation of esters
“Taking ethanol reacting with ethanoic anhydride as a typical reaction involving an alcohol: There is a slow reaction at room temperature (or faster on warming). There is no visible change in the colourless liquids, but a mixture of ethyl ethanoate and ethanoic acid is formed.”)
Results:
The distillation yielded sappy and lightly yellow tinted product that flows easily. It is very thin compared to thc distillate. It had no smell and no taste when vaporized.
I have stopped personal assay tests on it as psilisphical told me the product might be toxic still (I assume its because I did not neutralize it and there might be toxic AA left in it).
I yielded 9.9g of product, which gives an overall theoretical yield of 87%. I think if I neutralized the product and removed the acetic acid before the distillation I could improve yield.
Please let me know what you think.
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Well, it sounds okay, if you distilled off all the acetic anhydride before adding ethanol. The water most likely in the ethanol would react with the acetic anhydride to make the acid before ethanol could do anything. Iow, wet ethanol (or just 95% EtOH azeotrope with water) would essentially “neutralize” (i.e. make innocuous) the anhydride, turning it into vinegar, if there was only trace amounts of anhydride left when you put the wet ethanol in contact with the distilland (the Thc-o-acetate and friends left in the boiling flask after distilling off the acetic anhydride).
Although it can react with alcohols, it prefers to react with water, so that reaction would be faster. If there is too much anhydride in your distilland, it could react violently on contact with the water, creating heat that would drive the side reaction with ethanol… so don’t let that happen! 
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I want to note that I went on vacation for a week and when I got back to the lab my sample smelt like trace amounts of acetic acid. Looks like all of the AA or acetic acid was not fully removed from the sample in the ethanol transfer step. I ended up neutralizing the sample by dissolving it in pentane and washing it multiple times was salt water and then distilled water.
Summary:
In the future I would avoid using ethanol as transfer solvent due to reaction between AA and ethanol.
Neutralization is absolutely needed even when distilling final product.
PS: I would like to admit that @Psilisophical was correct that neutralization is needed.
Now on to the next project, Delta 8!
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keep us updated!
I was gonna say there is a patent release of this tek, But isnt the problem Finding the catalyst?
I placed a sample (2g) in a glass jar with a lid, in a dark drawer. It has been a month now and the thc acetate is still yellow, runny, and has the same effects as before. No acetic acid smell or taste at all. Still super smooth vapor. Looks like neutralizing step is essential for storage.
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Why would you want to synthesize anhydrous acetic acid? You would still need a catalyst to make that reaction work from what I understand. That is why I used acetic anhydride and refluxed for 3 hours.
I am under the impression anhydrous acetic acid is a controlled substance
It is a controlled substance but not that well controlled/regulated. I got a 500ml bottle of reagent grade for $50 on ebay. If you dont want to buy it I found this method (see link below) of synthesizing AA. It doesn’t call for sulfuric acid and I rather avoid the safety measures that strong acids call for. You also avoid the catalyst. Unfortunately if you avoid the catalyst you need to reflux the AA which requires an inert atmosphere. I used a consistent flow/blanket of nitrogen gas.
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