This is a contest. The winner will be given sexual compensation by a virtual Thai striptease dancer.
I guess a million bees have had a dream to use anethole (anise oil) as MDMA precursor. However, you don't need much chemistry knowledge to see that this is not an obvious synthesis. I have had the plan to perform the necessary syntheses, but I realize that I don't have enough time nor the necessary interest to end the project fruitfully. Hence this contest.
Using TFSE, I haven't seen anybody going into detail on how anethole can be used as MDMA precursor. What you will read now is semi-theoretical, from this point of view that I haven't performed the syntheses myself; but the necessary steps are all described in the literature, and that is what I am going to point at right now. Anybee who does have the time and interest to analyze the possibilities, please do so. You might be able to find improvements or combine 2 or more steps into 1-pot reactions.
Abstract: anethole is the main constituent of anise oil and can be oxidized to 4-methoxybenzaldehyde (aka anisaldehyde). This compound can be demethylated with a strong Lewis acid to obtain 4-hydroxybenzaldehyde. Mono-bromination of this benzaldehyde will yield 3-bromo-4-hydroxybenzaldehyde. The Br can be substituted for hydroxy, giving 3,4-dihydroxybenzaldehyde. Methylenation of this product yield piperonal. Piperonal can be a MDMA precursor in many ways.
Oxidation of anethole to anisaldehyde: There are several ways to accomplish this oxidation: sodium bichromate and potassium permanganate are the best known. I assume the experienced chemist has the necessary knowledge to perform this reaction. Some examples are available for isosafrole and asarone on Rh's website.
Ether cleavage of anisaldehyde: There are several methods to cleave the methoxy bond. The synthesis of 4-hydroxybenzaldehyde from anisaldehyde is described in the following articles:
- Ber Deutsch chem Ges 74 (1941) 1219 (with pyridine.HCl, 200-220°C)
- Ber Deutsch chem Ges 75 (1942) 350 (with pyridine.HCl, 200-220°C)
- J Chem Res Synop 6 (1999) 394 (pyridine.HCl, microwave)
- Synthesis (4) (1985) 437 (AlI3, PCT)
- Tetrahedron Lett 38(50) (1997) 8749 (1-methyl-2-pyrrolidinone)
I guess that the AlI3 method is one of the easiest ones. Check out
Post 422757
(GC_MS: "Aluminium iodide in ether cleavage", Methods Discourse) on how to make this otherwise very expensive compound yourself.
Monobromination of 4-hydroxybenzaldehyde:
- Tetrahedron Lett 21 (1980) 4931 (Br2)
- Arch Pharm 322 (1989) 477 (Br2, HOAc)
- Tetrahedron Lett 34 (1993) 7401 (Br2, CHCl3)
- Ber Deutsch chem Ges 28 (1895) 2410 (Br2, discusses dibrominated product as well)
Synthesis of 3,4-dihydroxybenzaldehyde:
-
Patent DE082078
(NaOH, 150-200°C)
-
Patent DE269544
(NaOH, Cu, pressure)
- Kogyo Kagaku Zasshi 47 (1944) 168 [CA 1949 1974] (NaOH, Cu)
Methylenation of 3,4-dihydroxybenzaldehyde is explained at Rh's website. Please refer to
https://www.thevespiary.org/rhodium/Rhodium/chemistry/methylenation.html
Iodination instead of bromination should work as well, I guess.
Voila, hopefully somebody sees something interesting in this. I am still convinced that vanillin is an easier precursor, which is equally unwatchable as anise oil. Good luck
.
A fellow bee already proposed the following:
Isn't the demethylation of 4-methoxy-benzaldehyde much easier than that of vanillin, making it possible to use refluxing 48% HBr (possibly with a PTC) for the ether cleavage step? As the molar weight of AlI3 exceeds 400, you need quite a lot of that to run a molar batch. After the reaction you just distill off the HBr azeotrope for reuse. Or - maybe it would be possible to add some H2O2 after the demethylation to make Br2 in situ and make the 4-MeO-BA -> 3-Br-4-OH-BA transformation a one-pot reaction. In that case the product is extracted with DCM, any residual bromine reduced with sulfite/phosphite or whatever, followed by recovery of the azeotrope.So, the aim of this thread is to combine The Hive Brains in an attempt to find a profitable way of turning anise oil into MDMA. It's not sure that this contest will end with good results, but as I know from my experiences in real life, you never know the outcome if sexual compensation is offered as reward. Theoretical AND practical information/remarks are welcome. Note that the given references are just
leads and that there might (and most probably will) be better solutions. It would be a nice thing if this thread could be concluded with the sentence on the back of Strike's TSII.