Author Topic: AlCl3 and Md compounds  (Read 33163 times)

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Kinetic

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Oh...
« Reply #20 on: January 27, 2003, 10:35:00 PM »
Thanks for the quick reply Rhodium, even though it wasn't what I wanted to hear! I had a feeling that would be the case, knowing the delights of letting a syringe block up with SiO2 within seconds of letting similar (to SnCl4) SiCl4 come in contact with air, and having heard that SnCl4 is packaged under argon...

I think a slight change of plan would be a good idea, which may not be too bad seeing as the article translated by Antoncho above adds the reagents in quite an odd order anyway. If someone who isn't me was to modify Kinetic's proven:

Preparation of butyrophenone

To 133.3g (1 mole) anhydrous aluminium chloride in 350ml anhydrous dichloromethane was added 106.6mL (1.02 moles, 108.7g) butyryl chloride. The mixture was stirred until all AlCl3 has been dissolved. With external ice-bath cooling, 89.8mL (1 mole, 78.1g) of benzene was added over an hour. Stirring was continued for an additional hour.
The yellow-orange reaction mixture was slowly added to 600mL stirred water/ice mixture; the pale lower layer was collected, and all volatiles were removed under vacuum.
The ketone was vacuum distilled, to give 1-phenyl-butan-1-one as a colourless oil.
Yield: 132.1g (89%)


by replacing AlCl3 with SnCl4 (obviously changing the other reagents too), would the solvation of SnCl4 by DCM slow the hydrolysis enough to allow the acylation to proceed? The first step in Rhodium's Indanylamphetamine synthesis has an excellent yield without any protective atmosphere :) .

BTW, that synthesis is from a two-step 1-phenyl-2-methylaminobutane synthesis which I'll post if anyone's interested. The second step only has a 40% yield, but it's very easy. Maybe other bees could have a play around with it; there's no doubt it would give methcathinone if propionyl chloride was used instead of butyryl chloride.


Rhodium

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Yup, here is a reference for that rxn
« Reply #21 on: January 27, 2003, 11:06:00 PM »
Reactant: benzo[1,3]dioxole, propionyl chloride
Product: 1-benzo[1,3]dioxol-5-yl-propan-1-one
Yield:   58 percent
Reagent: SnCl4
Solvent: CH2Cl2
Time: 1 hour
Temperature: 20°C
Ref: Journal; Daukshas, V. K.; Gaidyalis, P. G.; Pyatrauskas, O. Yu.; Udrenaite, E. B.; Gasperavichene, G. A.; Raguotene, N. V.;  Pharm.Chem.J.(Engl.Transl.); EN; 21; 5; 1987; 341-345; KHFZAN; Khim.Farm.Zh.; RU; 21; 5; 1987; 569-573.

Offline Whenimgone

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Re: A better way of Friedel-Craftsing.
« Reply #22 on: September 18, 2015, 04:26:19 PM »
Here's some useful info from the russian article Rhodium sent me yesterday. It talks about acylating various substrates, methylendioxybenzene among them.

The other ones are : <a href="https://www.thevespiary.org/rhodium/Rhodium/hive/hiveboard/picproxie_docs/000346121-file_fmw6.gif" title="View this image">[/url]

Here's the typical synthetic proc (all the same for each one, the only difference being the catalyst and the temperature.

<font color="blue">To a mixtr of 25mls unhydrous CH2Cl2, 37mmoles of the acylated comp'd, 37mmoles acyl chloride kept at specified temperature, there's added over the course of 0,5hrs 40mmoles anhydrous Friedel-Crafts catalyst. The rxn is further stirred 1h at 20 C, poured onto ice, acidified w/HCl , xtracted w/DCM, pooled xtracts washed w/water, dried and the solvt removed.

1,3-benzodioxole: catalyst - SnCl<sub>4</sub>, temp = 0 C
all the others: catalyst - AlCl<sub>3</sub>, temp = -10 C

Yield for methylenedioxypropiophenone - 58% (almost the worst of them all, generally the yields are 60-70%)
</font>


A great article, shall i say!


Antoncho

Any chance you could send me the link to this article?
Knowledge is free