04-14-04 11:59
No 500761
Does anyone know if Dr Drools synth will work with eugenol?
(Chief Bee)
04-14-04 18:09
No 500805
(Rated as: good read)
Unlikely. The wacker oxidation isn't fully compatible with Eugenol, see this article for details:
Anomalous Behaviour of Substituted Allyl Benzenes in Palladium(II) Catalysed Reaction
Meera Iyer, Dinesh N. Rele and G.K. Trivedi
Tetrahedron Letters, Vol. 30, No. 6, pp. 759-762 (1989) (../rhodium/pdf /eugenol.wack
Abstract
The Wacker reaction is one of the finest examples of transition metal promoted nucleophilic addition to olefins. An unusual observation has been made with regard to the normal Wacker process, whereby, the oxidation of eugenol (1) and methyl chavicol (2) does not lead to their respective carbonyl compounds. The reactions leading to the formation of two novel products and their mechanistic aspects are discussed.
The Hive - Clandestine Chemists Without Borders
(Stranger)
04-14-04 22:02
No 500831
Does anyone have any suggestions on which method(s) SWIM should use to demethylate/ methylate eugenol to safrole? Their are a couple of methods on rhodiums site but SWIM needs to know which one is the easiest for clandestine chemists with money and a limited amount of glassware.
(Hive Bee)
04-15-04 00:56
No 500863
Ive been trying to get that answer as well but with no luck. I think its bc not many, if any, bees have played around with the demethylation/methylation of eugenol. I could bee wrong but noone said i was, Post 500295 (homeslice: "future of safrole", Methods Discourse). I dont think many bees have tried to demethylate bc they havent had to as sassy oil is still available if ya look hard enough.
Never take a fox's word that the hens are safe.
(Stranger)
04-15-04 10:35
No 500926
Oh well
I'm trying
soon i'll post some results
I'm using more than 1 method, BTW
(including the new LiCl in DMF one)
I just don't like the part of adding 292 g of LiCl each time (4 times) it get's kinda expensive
Let God Die And Rot
(Faglord)
04-15-04 22:25
No 500984
This subject is very interesting, keep us all posted
of your results!
I think the most OTC and thus most doable method for
bees without access to chem suppliers would bee the
following. I was wondering what PTC to use, but I think
CTAB (thanks Kinetic!) should bee a good alternative.
So, to demethylate:
../rhodium /methyle
(maybee a substitute for cyclohexane)
to methylate:
../rhodium /methyle
I've got tissues with issues
(Stranger)
04-15-04 23:09
No 500989
I will try the AlI3 as well as the LiCL to demethylate
To methylate I'll use the
Methylenation Of Catechols with Dichloromethane in DMSO
as for the PTC, I bought TBAB, C and I (Tetrabutylammonium Bromide, Chloride and Iodide)
I know I2 is not OTC on the US of A, but my supplier's brand even has the method they used to produce it
(Panreac Brand) - from Chilen Nitrate
2NaIO3 + 5NaHSO3 ---> 3NaHSO4 + 2NaSO4 + I2
Hope this helped
"Ipsa scientia potestas est."
(Newbee)
04-16-04 23:25
No 501123
Excidium,
Are you going to use an inert atmosphere for the AlI3 method? Just curious because swim will attempt in the near future the AlI3 method while substituting toluene for cyclohexane, HTAB for PTC, and heating at bp of cyclohexane. Swim was wondering about your thoughts regarding the use of He gas as inert atmosphere.
This is very exciting, keep us posted!
Driven
It just seems to go faster...
(Hive Bee)
04-17-04 13:02
No 501258
Yep, it does seem that there is little first hand experience written up in this area.
Somebody once told me that a Methylenation of catechol with Dicholoromethane / Adogen 464 has been attempted with terrible yields so far.
112.5g DCM (1.125mol)/150g Water/3.75g PTC was refluxed under inert gas to reduce the amount of oxygen in solution.
75g (1.875mol) of NaOH in 375ml of water was repeatedly put under vacuum and then inert gas in order to remove the oxygen before 82.5g (0.75mol) catechol was added to from the catechoxide dianion solution (if you don't do this the whole lot turns black due to oxidation).
The catechoxide dianion solution was dripped into the refluxing DCM/Water over the course of 2.5 hours (inert atmosphere was used).
The reaction was kept under reflux for a further 2.5 hours.
Steam distillation of the reaction produced a 7% yield.
The problem was probably that the solution was refluxed, but not hot enough. DCM boils at 40C, so the reflux temperature was probably not much above this. Looks like you definitely need higher temperatures. Think it might be wise to use methylene bromide in place of DCM (rather than attempting to keep 112.5ml of DCM in the system whilst raising the temp to 90-95C -- imagine you'd need a hell of a reflux condenser to achieve that).
(Hive Addict)
04-17-04 14:40
No 501267
You did use good stirring, no?
If the mixture is not stirred well, then of course the PTC has little to no effect.
"It is the declared policy of the US Government to create a Drug-Free America by 1995."
(Hive Bee)
04-18-04 10:28
No 501444
The reaction mixture was stirried *hard* throughout on a good magnetic stirrer with a large egg-shaped stirbar. I don't think stirring was the problem (although I'm willing to be corrected).
(Hive Bee)
04-19-04 08:28
No 501571
starlight: is that recently that someone told you about that? if not have you heard anything else from that someone?
what would ppl think is the tougher of the two: demethylation of the eug. or the re-methylation of the catechol?
Never take a fox's word that the hens are safe.
(Newbee)
04-20-04 02:51
No 501692
Excidium,
Are you going to use an inert atmosphere for the AlI3 method?
Yeah, N2 on the way
And the yield here isn't that bad, i'm sure
and the methylenation shouldn't bee, too
A solution of 110 g of catechol, 120 ml of 50% aqueous sodium hydroxide and 200 ml of DMSO was heated to 98°C and stirred at that temperature for 30 minutes. This solution at 98°C. was added over a 30 minute period to a refluxing solution of 120 ml of methylene dichloride in 300 ml of DMSO. Thereafter, the reaction mixture was stirred at reflux for 1.5 hours. Steam was then passed into the mixture to achieve steam distillation of the product. The distillate (600 ml) was extracted with 100 ml of methylene dichloride, which extract was washed once with 50 ml of water. The methylene dichloride solution was then concentrated in vacuo at 40°C to yield 119.4g of a colorless oil. Gas chromatographic analysis showed 97.5% methylenedioxybenzene. Yield 116.4g (95.4%).
95.4% AIN'T bad
(the steam distill still give me the creeps... Ialways get the shivers to something I haven't done before)
"Ipsa scientia potestas est."