The next major category of precursors, apart from the phenylace-tones, are the p-Nitropropenes. One can see the two representative examples for X and meth in the little drawing below:
As you can see, there is a nitrogen right in the exact place where one wants it. That is definitely a step in the right direction. But Strike was not very keen on these intermediates because there was really only one decent way to make them that Strike favored and the ways to make final product out of them were not too hot as well. But a lot of things have changed for Strike in a year's time and there are a lot of new promises for this route.
So read what Strike has for ya here, then go to Rhodium's Chapter where some inventive new p-Nitropropene recipes can be found. Let's start things off with the basic recipe for this precursor.
METHOD #1: This section is going to be as thoroughly helpful to those interested in X production as it will be to those interested in amphetamine production. The process is known as the Knoeve-nagel-Walter condensation which can turn a substituted benzal-dehyde such as piperonal (X) or plain old benzaldehyde (speed) into an intermediate called a p-nitropropene. This intermediate can then be transformed into MDA (Benzedrine for speed) or MD-P2P (P2P for speed) depending on the capabilities of the chemist.
Both piperonal and benzaldehyde are List I controlled substances just as safrole and isosafrole are, but the speed maker has the advantage here because benzaldehyde makes up over 95% of the quasi-legal bitter almond oil whereas there is no natural source of piperonal. Piperonal, also known as Heliotropin, can be made from sassafras oil. It is also a very important chemical in the fragrance industry. But there are so many ways to make both it and benzaldehyde in the Build from Scratch section of this book that the Knoevenagel synthesis has a potential for resurrection from the heavy restrictions that the government has put on it. By heavy strike means that not only are the precursors controlled but so is the main processing chemical: nitroethane. This substance does have a wide use in industry such that the chemist may come across some in daily life (yeah, right) or the stuff can be made as described in the Chemicals section. In fact, we have quite a few more recipes for making nitroethane than before!
This procedure has been performed in a variety of ways [28 p714, 38-42] with variations in solvent, base and time of reaction. For piperonal conversion, the consensus is toward the use of acetic acid as the solvent, ammonium acetate as the base and 4 hours of reflux time. Dr. Alexander Shulgin, a giant in this field, prefers the use of cyclohexylamine as the base. Strike would not tend to doubt this man's choice, especially since Strike is also getting the feeling that ammonium acetate is heading towards the schedule I graveyard.
In a flask the chemist mixes 50g piperonal into 200mL glacial acetic acid, then adds 45mL nitroethane and 17g ammonium acetate. The solution is then refluxed 4 hours and takes on the color of yellow to yellow-orange. After 4 hours and cooling, yellowish crystals of p-nitropropene will spontaneously form. If not, the solution can be diluted with 50ml of dH20 and chilled in an ice bath for an hour to form the crystals with some slushy glacial acetic acid and water intermixed. The mass of crystals is broken up and plopped into a Buchner funnel to be vacuum filtered. The filter cake is washed with a little extra acetic acid or water. All of the filtrate is saved.
These p-nitropropene crystals the chemist now has can be air-dried and used as is, but that is not advisable. What they need is a little more cleaning up, and one does this by performing re-crystallization. To do this the chemist is going to use a solvent that everything in the reaction that the crystals came from is soluble in but that the crystals are not. Get it? No? Well, to demonstrate, the chemist will boil 200mL of methanol in a beaker and start knocking chunks of the impure p-nitropropene filter cake into the hot solvent. If all of the crystals will not dissolve in the 200mL of methanol then more is added and heated to accommodate. As soon as all the crystals are added and have dissolved, then the chemist turns off the heat and chills the mixture to 0-5°C. What is going to happen is that everything the chemist doesn't want will remain dissolved in the now cold methanol, but all of the p-nitropropene crystals will 'recrystallize' when cold. This solution is now vacuum filtered and the now clean crystal filter cake is washed with a little bit of extra, cold methanol just to make sure. That extra methanol washing and the filtrate can be reduced in volume by distillation and chilled to retrieve a second crop of p-nitropropene crystals (total conversion is around 70%). The final thing to add is that the chemist has a choice of recrystallization solvents other than methanol. These include hexane, isopropyl alcohol and ethanol.
You know how just a couple of paragraphs ago where the chemist first filtered the crude crystals from the chilled reaction mixture, then washed them with water or acetic acid? Well, all that liquid filtrate has a lot of valuable, unreacted piperonal or benzaldehyde in it. To rescue the stuff the chemist dilutes the mixture with 500ml dH20 and extracts it with DCM. The DCM is washed with 100mL 5% NaOH solution then vacuum distilled to give a dark oil which is unreacted aldehyde. Hey! That's a lot of good material that can be put through the process again.
There are some slight alternatives to this process that, for educational reasons only, Strike is going to lay out for you now.
(1) It has been shown that by doubling the amount of nitroethane respective to that of the aldehyde in a ratio of 2 to 1, then the amount of ammonium acetate used can be reduced considerably [28 p703],
(2) The cooled reaction mixture can be induced to crystallize its p-nitropropene payload by simply dumping the whole thing in a large volume of ice water ,
(3) Once the reaction mix has cooled after reflux, 500mL of room temperature dH20 can be added and the whole solution extracted with DCM. The DCM layer is separated and the solvent removed by distillation to give the IJ-nitropropene as an oil of all things. This oil can then be recrystallized in hot methanol just like the crystalline form was ,
(4) Russian articles make some outrageous claims and this one is no different , These mothers claim that piperonal or benzaldehyde will react with nitroethane by sitting in the dark at 10DC with only a couple of drops of ethylenediamine. Almost 100% yield no less! Strike has never tried this nor does Strike fall for Russian science, but if anyone is interested...
Once one has the (3-Nitropropene, there are two ways one can progress. One can take the P-nitropropene and convert it into final, pleasure-inducing product. Which you can read about in the next section. But the other option for processing p-nitropropenes is to turn them into P2Ps. The chemist has to do something with the stuff because if it sits around too long it's going to degrade. This
procedure is really easy and has high yields [28 p734-735], 32g elemental (electrolytic) iron (Fe) and 140mL glacial acetic acid are heated in a flask or beaker to around 60°C or, in more vague terms, to the temperature that is as hot as possible without the formation of white precipitates. One might want to do a couple of dry runs to determine the correct temperature. Into the hot mixture is slowly dripped a solution of 10g MD-nitropropene (that's the P-nitropropene made from piperonal) and 75mL glacial acetic acid. The dripping is adjusted so that the reaction does not become too violent or foamy. The color of the reaction will progress from orange to a deep red with the formation of white salt precipitates. After addition the solution is heated for an additional 1.5 hours at 70°C "during which time the body of the reaction mixture become^) quite white with the product appear(ing) as a black oil climbing the sides of the beaker"[28, thanks Dr. Shulgin], When cool, the reaction mix is added to 2L of dH20, extracted 2 times with 100mL DCM and the DCM extract washed with 1N NaOH solution. The DCM layer is vacuum distilled to give ~8g of pale yellow MD-P2P. Strike must say that that was a pretty easy one-pot procedure using 2-3 simple chemicals with an 80-90% yield.
METHOD #2: This may work on safrole but Strike has never tried it on the molecule. This should make good use of isosafrole and its cis isomer . 76g silver nitrate (AgN02) and 254g iodine (find this at some pharmacies) are stirred in 600mL ether for 30 minutes, then 82g isosafrole in 100mL ether is dripped in while a gentle breeze of nitrogen from a baby nitrogen tank is blown into the air space of the flask. The nitrogen displaces atmospheric oxygen from the flask so that it won't mess with the reaction mix. The solution is stirred at room temperature for 4 hours, vacuum filtered, washed with a solution of dilute NaHS03 then washed with saturated sodium chloride solution. The ether is separated, dried through Na2S04 and removed by simple distillation to afford a dark oil residue which is an iodo-nitro intermediate (don't ask). Now, Strike could be wrong (and often is) but the way this article reads gives Strike the distinct impression that the conversion of this intermediate to the final p-nitropropene can occur in two different ways. The implied way is to add 300mL ether and 300mL pyridine to all of the intermediate oil sitting by itself in the flask and
stir it at room temperature for 2 hours. The nitrogen in pyridine plucks the iodine off of the intermediate causing an elimination (don't ask). The solution is extracted with a large volume of pen-tane and water. The pentane layer is washed repeatedly with fresh dH20, dried through Na2S04 and vacuum distilled to give product at +50% yield. The other way this may be done is listed a couple of paragraphs up in the article in the section titled 'Preparation of 3-Nitro-2-cholestene'. To the intermediate oil is added 11 g silver oxide powder and 500mL methanol and then refluxed for 4 hours. After cooling, the solution is vacuum filtered and the methanol removed by distillation to give product (99%?). There is also an interesting, simple zinc reduction of the nitro product to ketone. Could this be another way to make P2Ps from p-nitropropenes instead of using Fe that is detailed in Method #1? Eleusis seemed to think so when asked. So here is the experimental as written in the journal article. Just imagine an equal amount of p-Nitropropene in place of the '3-Nitro-2-cholestene' and P2P as the product:
"Reduction of 3-Nitro-2-cholestene . - Zinc dust (800mg) was added in portions during 1 hr to a stirred warm (40°C) suspension of 250 mg of 3-nitro-2-cholestene in 15mL of acetic acid and 0.5 ml of water. After 4 hr reflux, the mixture was filtered hot and the zinc washed well with hot HOAc. Addition of water and extraction with ether gave 116mg of product."
METHOD #3:[45-47]—Do not try this method! Strike repeats, do not try this method! This is the method popularized by Dr. Shulgin and reported in some of the underground literature  which uses the most dangerous compound in drug conversion chemistry that Strike is aware of: tetranitromethane. The reason this method keeps hanging around is because one can get clean, hyper yields of p-nitropropenes in less than 5 minutes. But the ultimate method can exact the ultimate price (death, bubba!). Rave rats are very idealistic and figure they can tangle with this method if they are careful. And since Strike cannot undo the presence of this procedure in the literature or the determination of enthusiastic chemist to try this, no matter how much they are told not to, then Strike will at least lay down the proper way it is accomplished.
There is an incredible amount of energy in the carbon-nitro bond. TNT (trinitrotoluene) has three such bonds. Tetranitromethane has four! Starting to get the picture?
Tetranitromethane was used as a double bond detector and for the detection of tyrosine in protein sequences. As you can guess, isosafrole's double bond is the point of attack. The problem is that there is not any accessible chemical company today that makes this compound anymore. So the rave rat is going to have to make it herself, and that's where the trouble begins. The best method for making tetranitromethane is in Organic Synthesis  using fuming nitric acid and acetic anhydride. All the glassware is cleaned with soap and hot water, rinsed thoroughly with distilled water, rinsed with acetone then rinsed once more with distilled water. The glassware is placed upside down on a sheet of foil in an oven and baked at 425DF for 1 hour. Baking destroys any remaining organics which can set off the tetranitromethane to explode. This glassware washing procedure, by the way, is the preferred way to wash up all of one's glassware after a long day's experimenting. It is the same procedure used by all the organics labs that Strike has been fired from.
The apparatus to use is seen in figure 13 which consists of a burette, thermometer, Erlenmeyer flask and a two-holed rubber stopper that has a small V-shaped wedge cut out of one side of the rubber stopper to allow the inside contents to vent. 31.5g of orangy-red fuming nitric acid (see chemicals section) is poured into the Erlenmeyer flask and the rubber stopper with its burette and thermometer is placed on to the
flask. The HN03 is cooled to below 10°C with an external ice bath and is never allowed to go above 10°C for the entire addition. 51 g of acetic anhydride is poured into the burette and a big pane of clear acrylic that the chemist buys at the home improvement store is placed between the chemist and the apparatus to act as a blast shield. The acetic anhydride is added in small little squirts or slow dripping to the cold, stirred HN03. The solution will not change color throughout the addition. When the addition is complete, the burette is removed from the stopper but the solution continues to stir in the ice for another 4-6 hours then it is slowly allowed to come to room temperature by allowing the ice to melt. Once at room temperature the flask is removed from the stirplate and the solution should be monitored closely for at least 3-5 more hours. If the temperature of the solution starts to rise above room temperature during this time, then the ice bath must be reapplied. If the temperature starts to skyrocket then run. After monitoring, the stopper and thermometer are removed, the flask covered with an inverted beaker and stored behind the blast shield in a dry, dark place for 7 days.
After 7 days the solution is poured into 300mL cool dH20 in a 500mL flask and slowly distilled with no vacuum. The first 20mL of distillate that comes over will be clear heavy tetranitromethane. The chemist will know that all has distilled over when the last clear drops that come over will be water that will start to form a layer on top of the tetranitromethane. The product is washed with dilute NaOH, then water and dried through a very small amount of Na2S04 to give 16g pure tetranitromethane.
With tetranitromethane in hand, the chemist proceeds to convert isosafrole to p-nitropropene at an astonishing speed. 41 g isosa-frole, 300mL anhydrous acetone and 24g pyridine are well stirred in a flask and cooled to 0°C by means of an external ice bath (everything behind a blast shield of course). 54g of tetranitromethane is cooled to 0°C and then quickly poured into the reaction flask. The solution is allowed to react for exactly 2 minutes and then the reaction is immediately stopped by adding a mixture of 16.8g KOH in 300mL dH20. The temperature will have risen during the 2 minutes of reaction and the stoppage, so it is allowed to stir and
chill back to around 0°C. As the solution chills, p-nitropropene crystals will form and can be removed by filtration. The filtrate can be extracted with DCM and the DCM removed by distillation to yield an additional crop of crystals. The yield is about 50g (90%). These crystals are clean enough to convert into MDA or MD-P2P.
Now Strike is going to tell you a story. Once upon a time there was a beautiful kingdom of wealth and good will because God, in his infinite wisdom, had seen fit to bless the land with an abundance of bee pollen. It was the want of 49% of the citizenry to partake of this bee pollen because it made them happy. One day an army called The Majority invaded the kingdom and took seize of the bee pollen. You see, The Majority did not like bee pollen. In fact, the majority disliked bee pollen so much that not only would they not eat bee pollen themselves, they could not tolerate the idea of others eating bee pollen as well. There was much despair in the kingdom among those who liked bee pollen and many lamented their own fate. Some citizens became angry that those with might would impose their will on others. So those angry citizens took to tending bees in their cellars. It was of great expense to conduct such an undertaking and it forced many a citizen to forfeit a week's wage to obtain what they had once had for free. The Majority soon discovered that not only did many of the citizens have a distaste for the law against bee pollen, but that many citizens would break the law just to ingest bee pollen even though they were forbidden to do so. This affront angered The Majority so much that they decided to actually imprison citizens who ate bee pollen. The enormity of such a task soon became apparent as millions upon millions of citizens were sent to languish in dungeons for eating bee pollen. Confident in their cause, The Majority continued the inquisition unabated.
Meanwhile, in a stately laboratory atop a hill, the second finest alchemist in the land cast her sight beyond her potions and upon the landscape below. The troubles in her land prompted her to speak aloud, "How have things come to this? Although I am pleased for the good fortune that has come to my friends who contract and build dungeons, and who enforce the bee pollen laws, I cannot help but feel that...that...aw fucketh it!". And for no
reason at all, the chemist decided to make tetranitromethane. The chemist made a 5X batch of the stuff and had just set the flask to incubate for 7 days behind a blast shield in a bathroom of the house. Being the second greatest chemist in the land meant that the procedure had been performed perfectly under the strictest of conditions. And then, without any warning, the unattended solution decided to spontaneously get hot. The resulting explosion produced a shock wave so powerful that the tiles were ripped from their foundation as the blast plowed through the bathroom door, down hallways, around corners and shattering its way through half the windows of the house.
Strike thinks you get the picture now. Do not try this method. How did the story end you ask? Strike doesn't remember exactly. Strike thinks the kingdom was re-invaded by the forces of the neighboring Bee Keeper Empire.
Continue reading here: Bromosafrole Phenylisopropylbromide
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