Thanks for your replies; especially the organocadmium link which has saved me a lot of time and money before attempting the synthesis, which I now think may be doomed to failure. The document mentions that both organocadmium and organozinc reactions run much better in hydrocarbon solvents than they do in most ether solvents, due to ester formation between the acid chloride and the ether. Since benzodioxole is an ether, and possibly a more reactive one than most (it seems to be a lot easier to demethyleneate than other aromatic ethers are to demethyate; Shulgin acylates a number of aromatic ethers in high yield using AlCl
3 as the catalyst, which would destroy benzodioxole), won’t ester formation between benzodioxole and propionyl chloride be a significant side reaction, enough to invalidate this route? So that may be another methylenedioxypropiophenone synthesis down the drain…
What I have just noticed though, and I can’t believe I missed the first time round, is the acylation of benzodioxole using tin tetrachloride as the catalyst - in
Post 361935
(Rhodium: "Everything you need for methylone.", Novel Discourse), Rhodium mentions an article which gives 58% yield of methylenedioxypropiophenone, which is fantastic considering the terrible results I’ve had so far. Here is the abstract:
Reaction 16 of 34
Reaction ID 1651712
Reactant BRN 115506 benzo[1,3]dioxole
385632 propionyl chloride
Product BRN 165729 1-benzo[1,3]dioxol-5-yl-propan-1-one
No. of Reaction Details 1
Reaction Classification Preparation
Yield 58 percent (BRN=165729)
Reagent SnCl4
Solvent CH2Cl2
Time 1 hour(s)
Temperature 20 C
Ref. 1 5702207; Journal; Daukshas, V. K.; Gaidyalis, P. G.; Pyatrauskas, O. Yu.; Udrenaite, E. B.; Gasperavichene, G. A.; Raguotene, N. V.; PCJOAU; Pharm.Chem.J.(Engl.Transl.); EN; 21; 5; 1987; 341-345; KHFZAN; Khim.Farm.Zh.; RU; 21; 5; 1987; 569-573.
So would ‘Pharm.Chem.J’ be ‘Journal of Pharmaceutical Chemistry’, and contain an English translation of the entire article? I don’t know if I have access to this journal, but if someone could confirm the name I’ll have a look tomorrow if possible. If it's as simple as it looks, I suspect it will be the best route to methylenedioxypropiophenone from benzodioxole.
[
Edit: ‘Pharm.Chem.J’ is an abbreviation of 'Pharmaceutical Chemistry Journal'. No wonder I couldn't find it... I'll have another look in the library soon, since it's only available online from 2000 onwards.]
Rhodium, I would love to attempt synthesising P2P from dimethyl cadmium and phenylacetylchloride, but due to certain factors beyond my control (3 in fact; the toxicity of cadmium and it’s salts, the legal status of the finished compound, and my incredible lack of money), I doubt I ever will. If I ever get the chance, I would try synthesing phenyl-2-butanone using diethyl zinc and phenylacetylchloride, just to see what would happen.