possible one pot shot from isosafrol to mdma

[PrimoPyro]

Ok, this thread is hereby changed into the photoamination of propenylbenzenes thread.

I read the patents at the bottom of the document, and am convinced that this is a wonderful process. Here are some interesting notes.

1.This process works to use ammonia or a primary or secondary amine, in conjunction with an olefin, to produce aliphatic, cycloaliphatic, heterocyclic aliphatic, or aromatic mono-, di-, and tri- amines. That is a huge spectrum of possibilities!

2.Patent number 2,749,287 deals with the addition of ammonia to aromatics, specifically benzene, toluene, and xylene, to produce aniline, toluidine, and xylidine plus hydrogen. This is not addition across the double bond, but a substitution for tacking on an amine.

3.Technically speaking, catalysts are optional. They do greatly increase yields, but the reactions proceed without their use. You really need to read the second patent, the catalyst list is huge. (thats good, for those here that dont know)

4.The wavelength of light is said to be preferrably 1600-2200A (Angstroms?) and to use other wavelengths, a photocatalyst must be employed. At this wavelength, no catalyst is needed for the reaction to take place, but it is recommended.

5.This frequency range presents a minor issue on glassware. Quartz glass does not allow too much radiation of those wavelengths to pass through, but siliate glass works perfectly. Specifically types: Corning #7940, Suprasil^(R). No prob, who uses quartz glassware??? Borosilicate pyrex should be fine.

6.Examples of lamps that produce light with the desired wavelengths are: Deuterium Lamps, Mercury Argon Lamps, and Xenon Flash Lamps. They say the xenon lamps are by far the best. Keep in mind this is for optimum wavelength.

7.Here's the good stuff! A list of organocatalysts used in these reactions. These are so simple! Examples: Ketones (they outright said they preferred acetone), Diacetone alcohol, Pyridine, Several Phosphines (read the patent), Benzene, and M-Xylene! Meta-xylene and acetone are what really caught my eye. Over the counter xylene is mostly the meta isomer, and the three isomers can actually be seperated if you want to.

8.Optimum temperature range is -10°C to 40°C, and I quote, "...but any convenient temperature may be used." Sheesh, "ya do whatever you want it'll work" Sounds good to me.  

9.Ratios of amine to olefin: can range from 1:1 to 20:1. They say preferred ratios are 5:1 through 15:1. I'd agree, not just to get the reaction to proceed, but to minimize multiple additions of your newly formed amine to another propenylbenzene.

It says that the catalysts only need be present in catalytic amounts (no fucking shit) but is generally limited by the properties of solubility of the catalysts and reactants.

This patent seems to deal with the same concept drone discussed, but makes no mention of p-DCB or acetonitrile, makiing me wonder if the reaction is indeed not so specific to those reactants.

Personally, I'd think that using an organocatalyst as a solvent would do wonderful, such as acetone or m-xylene, or a solution thereof.

So really the only question I cansee as to which catalytic solvent you use, would be to use the one that offers the highest solubility for amonia or methylamine, so you can saturate it as much as possible.

I have one question that I'd really reallyreally like someone smarter than me to answer, if you don't mind. Would it be feasible to prepare a solution of methylamine in a nonpolar solvent by reaction of methylamine salt with base IN THE NONPOLAR.

I know thatthese compounds are not soluble in nonpolars, but the reaction should proceed, as by basic rules anyway. It will produce water. So for example, specifically, if SWIPP had some acetone with MgO crystals in it, and added some methylamine sulfate, would it react to form methylamine gas and magnesium sulfate, which will suck up the water and crystallize? You could then filter your nonpolar to remove the solids, and use it for immediate reaction.

The point is not to prepare a mere methylamine solution, it is to prepare a solution beyond the saturation point. (I assume it'd just start fuming)

                                                   PrimoPyro
Vivent Longtemps la Ruche!

[PrimoPyro]

The shortest wavelengths for ANY of these lights that I can find examples of are around ~350nm, or 3,500A which is less energy than required to proceed without a catalyst. Sodium lamps produce around ~589nm, Hg around ~549, and xenon flash ranging from ~350-800nm, all are too low in energy. (remember shorter wavelength = higher frequency = more energy)

A catalyst is going to be necessary to carry these reactions out. However if a catalyst (or several) are used, then any of these lamps, since their affects are so similar could be used. The highest recommendation in the patent was for the xenon flash lamp, undoubtedly they were referring to the higher power kind, not one producing a shitty 800nm.

So personally, I'd say go for the Xenon flash lamps as long as you can find one with enough wattage to get the job done. I think a large one would be quite expensive, whereas a sodium bulb that produces ~589nm at over twice the lumens experimented with, will only cost ~$20.00 USD.

EDIT: Found a Hg lamp at ~360nm, so I know they get that powerful. I think a thin tubular Xenon lamp (strobing) the thickness of slightly larger than a pencil, actually suspended (maybe two or three even) into the reaction mixture would provide the best results, as long as you protected the bulbs from direct contact (coat them in something). This would also solved the problems of the correct glass worry, as the rays do not have to pass through any glass to reach the reaction mixture, and also the rod will not overheat, as the reaction mixture is cooled to 10°C, which keeps the rods cool.

To do it this way, with a suspended rod tube, you obviously couldnt do it in a flask, keep that in mind.

                                                   PrimoPyro
Vivent Longtemps la Ruche!

[halfapint]

Real prodigious, Primo.

Got a possible issue on the glass types. Suprasil isn't exactly a silicate glass; it's a fused silica glass. Like fused quartz, it's composed of little but SiO2, not sodium silicate or borosilicate. To say "Borosilicate pyrex should be fine" may not bee entirely accurate.

Here's one alternative: "quartz" heaters have nice (fused) quartz tubes enclosing nichrome heater elements. I know your patent source complained about its low transparency up around 160 nm, but that is the best you're going to find, without directly subsidizing your glassmaking conglomerate with big bux. Quartz does approach the short wavelength passband of interest; in other words, it gets close enough to work. Fused silica of course is best, but does not grow on trees and cannot bee found in garage sales. Other glass types, I'm afraid, are way out of the picture. If somebody has a big natural quartz crystal, plus the equipment and skills to bore it out, that presents another possibility to make a vessel for short-wave UV reactions.

This is the situation as I understand it: fused silica is best; fused quartz is better than nothing; all other glass is nothing. Sorry. The only option remaining is working in an open container, with the UV light source over it.

Thank you very, very much for the tips on acetone and m-xylene. Most appreciated. Didn't want to fool with dicyanobenzene, plus have a distinct recollection of some bee pushing the m-isomer in preference to p-DCB, which added to my confusion.

Edit: Second time today I had a post I was working on, beat to the wire by another poster. The xenon flash lamps which are so highly recommended, are those used to excite ruby, YAG, or other solid-state lasers. This isn't the same as your photographic flash units!
turning science fact into <<science fiction>>

[PrimoPyro]

Here's some more good information on the details of this reaction:

1.Another catalyst specifically stated to projmote this reaction is ammonium bromide and/or iodide. Iodide is much preferred.

2.I quote, ""In general, the mole ratio of ammonia or amine to photocatalyst is 20:1 to 500:1 with a ratio of 100:1 to 400:1 being preferred."

3.I quote, ""It has been found that any light absorbing-ketone impurity which may be present in the amonium halide as a result of the method of its manufacture must be removed, usually by salt recrystallization, since such impurity substantially affects the olefin conversion to amine."

4.I quote, ""It has been found that ammonium chloride and amonium flouride are promoters and not true catalysts since their use produces no more than a stoichiometric yield of product."

Now am I correct in nderstanding that that translates to: Moles amine produced = or < moles halide employed. That's what that means right? Yuck.

5.I quote, ""Double bonds adjacent to groups that can stabilize free radicals are said to activated, and these generally react much more readily than unactivated double bonds."

Interesting, and good to remind yourself of, but this applies to all kinds of reactions involving olefins, so it's nothing earth-shattering.

6.This is great! They answered a question in my mind about increasing solubility: What about PTCs?

Well we all have our lovely quaternary ammonium salt PTCs that we all love so much, and guess what! They are employed here!  

To increase the solubility of the catalyst and the amine so that they can more readily react with the olefin, a quaternary ammonium phase transfer catalyst is employed, as long as it does not interfere with the reaction.

Preferred PTCs are tetra-alkyl ammonium bromides and iodides, more preferrably iodides.

Specific favorites: "Especially tetra-n-butyl ammonium iodide, and tetra-n-heptyl ammonium iodide."

They also mention that the chloride catalyst forms the hydrochloride salt of the produced amine and is harder to isolate, but I really think they were referring to isolating the hydrochloride for reuse, not isolating the product of the reaction.

                                                   PrimoPyro
Vivent Longtemps la Ruche!

[PrimoPyro]

O yea, and the photoamination proceeds "at any convenient pressure."

Specific parameters are between 0 and 600 PSI. Preferred pressure is 100-400PSI. (Mods, don't jump down my throat for nonmetric units, they are stated in the patent as such)

I was wondering if there might be a way to make this mechanism enantioselective? That would be awesome, being able to tweak optical isomer formation... But alas, the very concept of such catlysis is beyond my grasp at this point. But I wanted to bring the idea up.

                                                  PrimoPyro
Vivent Longtemps la Ruche!