Check this out
Facile and fast pinacol rearrangement by AlCl3 in the solid state.
Abstract
A facile and efficient synthetic procedure for effecting the pinacol rearrangement catalyzed by AlCl3 in the absence of solvent is developed. The rearrangement product is obtained at room temp. in a few minutes and in almost quant. yield. Benzylic pinacols rearrange under these conditions, while aliph. pinacols do not react.
http://www.mdpi.org/molecules/papers/60500442.pdf (http://www.mdpi.org/molecules/papers/60500442.pdf)
I can't tell if it will yeild the desired ketone or propiophenone? I think it will bee the right one. Damn why didn't they do one more experiment.
Will AlCl3 tear apart the MDO ring?
Here is something also worth looking into for ketone preparation possibilities. Maybee even a whole new route to MDP2P from the dihalide, if the dihalide of safrole rearranges to the ketone it would bee even better!!!
Kakis Rearrangement: A series of organic laboratory experiments.
Field, Kurt W.; Moroz, Judith S.
Abstracts of Papers, 222nd ACS National Meeting, Chicago, IL, United States, August 26-30, 2001 (2001), CHED-426. Publisher: ACS
Abstract
We have developed a microscale org. lab. expt. which illustrates the Kakis rearrangement and related reactions. The Kakis reaction, which is comparable to the pinacol rearrangement, involves the silver ion promoted rearrangement of vic-dihalides to aldehydes or ketones. For example, the reaction of 1,2-dichloro-1,1,2,2-tetraphenylethane, 1, with silver ion and water is solvent dependent. In aq. (.apprx.1%) methanol, 1 gives 2,2,2-triphenylacetophenone almost exclusively. However, in aq. (.apprx.11%) acetone, 1 affords near quant. yields of tetraphenylethylene oxide. An efficient prepn. of 1 from tetraphenylethylene was also developed which eliminates the use of cylinders of chlorine and chloroform solvent. These transformations illustrate a no. of important mechanistic processes; details of the expts. will be presented.
Those who give up essential liberties for temporary safety deserve neither liberty nor safety
Well, I distilled off the DCM and tested with bisulfite. Negative. I tested by trying to form the oxime. Negative.
So I distilled the oil. At 120-200C I got 5.1g forerun (more dense than water), at about 272-278C I got 22.6g. I pulled it off the heat, and maybe 3g was left in the flask. I tested the main fraction with bisulfite. Negative.
Conclusion: the main fraction is not ketone, I don't think it's the acetyl glycol as that normally smells of acetic acid after distillation, so it's most likely glycol. This fits because anethole's BP is 235, the anethole ketone is 268C, so it makes sense for the glycol to be 278C.
This means a couple things:
1) dilute tosic acid in methanol doesn't work to rearrange the glycol
2) distilling glycol does not rearrange it to ketone
This is not to say the technique doesn't work with the epoxide. Who knows? This is not to say that distilling formyl glycols does not rearrange them. Twodogs said in Post 229901 (https://www.thevespiary.org/talk/index.php?topic=11411.msg22990100#msg22990100)
(twodogs: "Re: Ketones from Propenylbenzenes via the di-bromides", Novel Discourse) that it works. Remember the reason Horing wanted to check out the epoxide rearrangement by boiling? It wanted to prove that the rearrangement was an intramolecular transformation (not one catalyzed by minute amounts of acid). Perhaps a small amount of H2SO4, p-tosic, or even formic acid from the formyl glycol could be used to catalyze the rearrangement.
PS. When attempting the oxime, I got some white precipitate that definitely wasn't the oxime... what is that stuff? I talked of it in other threads, perhaps some sodium sulfate or something?
PPS. The glycol withstands heat alright, it showed only a very mild discoloration after heating to ~280C for 20 minutes.
For further study: I also wonder if adding just a couple drops of sulfuric acid would bring about the rearrangement of the 20.0g. I'll have to try that!
Well, I finally am ready for another idea... how does this sound to people?
I was thinking about doing a 100mmol batch of the peracetic (glycol from 16.2g isosafrole) in 100ml toluene using 1.0g tosic (same 1% acid solution, but reduced volume than the reference in Post 264135 (https://www.thevespiary.org/talk/index.php?topic=11605.msg26413500#msg26413500)
(Scooby_Doo: "Ref on Isosafrole to diol via electro", Novel Discourse)).
I plan to make the tosic acid in situ as needed, by slowly refluxing 0.57g of 90% sulfuric acid in 100ml of toluene using a dean stark, when that's done, then to add the glycol and continue the reflux for 20mins. I know toluene refluxes at a higher temp but I hope everything will be OK. Then wash with 10% NaOH and distill the ketone.
Does this sound alright to everyone? Would using that huge excess of toluene stop the sulfuric acid from reacting? If so, this seems like a nice easy way OTC way to do the rearrangement. (minus the unusual piece of glass...)
Some detail is in Post 344100 (https://www.thevespiary.org/talk/index.php?topic=9840.msg34410000#msg34410000)
(Chromic: "OTC tosic acid rearrangement SUCCESS!", Methods Discourse). I've got the oxime in the freezer, it doesn't look like it has fully crystallized yet. Perhaps it won't. I'll vac filter tomorrow and let everyone know.
CN1201776
Abstract
A process for synthesizing p-cresol by direct alkali fusion of p-toluenesulfonic acid includes such technological steps as preparing p-toluenesulfonic acid by sulfonating reaction of toluene on sulfuric acid, direct alkali fusion of p-toluenesulfonic acid with fused sodium hydroxide to obtain cresol sodium, acidifying it with SO2 to obtain coarse cresol and then separating to obtain p-cresol. Itsadvantages include no need of neutralization step, less consumption of energy and raw materials, short reaction time reduced by 4/5, and high output rate increased by 10%.
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I found the above patent at http://gb.espacenet.com/ (http://gb.espacenet.com/)
, but it's only the abstract. Anyone know where to find the complete specification? Peace! 8)
Love my country, fear my government.
No, I can't read mandarin, smart ass. I just thought I'd throw it out here just in case there's an english text article floating about somewhere, or maybe there are equivalents. I can't find any other patents that are geared specifically towards the production of p-tosic acid, just halogenated stuff.
For whatever it’s worth, p-tosic acid’s soluble in DMSO
”Other suitable organosulfonic acids will be readily apparent to the skilled of the art. The most preferred organosulfonic acid is para-toluene sulfonic acid (p-TsOH), in view of its wide commercial availability, low cost, and high solubility in the sulfoxide solvents of the invention.”
http://l2.espacenet.com/espacenet/viewer?PN=US4304681&CY=gb&LG=en&DB=EPD (http://l2.espacenet.com/espacenet/viewer?PN=US4304681&CY=gb&LG=en&DB=EPD)
UPDATE: Check this out; http://l2.espacenet.com/espacenet/viewer?PN=US4242275&CY=gb&LG=en&DB=EPD (http://l2.espacenet.com/espacenet/viewer?PN=US4242275&CY=gb&LG=en&DB=EPD)
Another; http://l2.espacenet.com/espacenet/bnsviewer?CY=gb&LG=en&DB=EPD&PN=US3458449&ID=US+++3458449A1+I+ (http://l2.espacenet.com/espacenet/bnsviewer?CY=gb&LG=en&DB=EPD&PN=US3458449&ID=US+++3458449A1+I+)
More; http://l2.espacenet.com/espacenet/bnsviewer?CY=gb&LG=en&DB=EPD&PN=US2841612&ID=US+++2841612A1+I+ (http://l2.espacenet.com/espacenet/bnsviewer?CY=gb&LG=en&DB=EPD&PN=US2841612&ID=US+++2841612A1+I+)
http://l2.espacenet.com/espacenet/bnsviewer?CY=gb&LG=en&DB=EPD&PN=US2828333&ID=US+++2828333A1+I+ (http://l2.espacenet.com/espacenet/bnsviewer?CY=gb&LG=en&DB=EPD&PN=US2828333&ID=US+++2828333A1+I+)
Peace! 8)
Love my country, fear my government.