Sodium Borohydride NaBH4

[151]—This catalyst should really be purchased rather than made because its use in underground chemistry is limited and is hardly watched at all if not ever. This may change considering its potential as a precursor to the NaBH3CN in Strike's #1 method of choice. There are a lot of ways to make this catalyst, but the least involved is the one using boron trifluoride. What the method calls for is an apparatus called an autoclave. You know how using a vacuum causes the absence of pressure to make things boil at a lower temperature? Well, an autoclave is a device that causes an

increase in pressure so that things will get to a higher temperature without boiling. Yeeshl This is already starting to sound complicated and, yeah, Strike guesses it kind of is. But there is a little price to pay for total independence from government scrutiny.

All biology labs and hospitals have autoclaves for sterilizing their equipment so if the chemist has access to one then all she needs to do is place the reactants in a flask, cover the flask with foil and blast them in an autoclave for a few hours. This, however, is probably not feasible so about the best thing Strike can think of for home use would be as follows. Still, Strike is not entirely sure if this apparatus is a correct one, and if the chemist also has some doubts then she would probably want to ask a professional research chemist who has used autoclaving as a synthetic tool. Strike's idea is to use a pipe bomb with a special fitting so that pressure from a pump can be introduced into the bomb. Most vacuum pumps are reversible so that they will produce pressure as well as vacuum. How much pressure? Well, that is something the chemist is going to have to look up because it was not provided, and Strike does not want to look it up either. It is suffice to say that one is going to use as much pressure as is necessary to bring an ether solution to 120-130°C without it boiling.

7.9g sodium hydride (NaH) and 100mL of a 0.05M solution of boron trifluoride etherate (0.4g BF3 in 100mL ether, this usually must be purchased as a commercially made product)is placed in a pipe bomb. Pressure is applied and the bomb is placed in a 120-130° oil bath for 2 hours. The ether is removed under vacuum and the NaBH4 is isolated by recrystallization from water. To do this the chemist adds water to the residue which causes the NaBH4 to crystallize out as a dihydrate precipitate. This white precipitate is separated as a filter cake, washed with a little water and the filter cake is vacuum distilled to remove the dihydrate water molecules that are attached the catalyst. This dry NaBH4 is now suitable for use. Although Strike is again not sure, Strike thinks it might be possible to attempt this in a plain old sealed pipe bomb without the pressure addition.


[152]—This catalyst has not been given a fair shake in underground literature and, as of this book's printing, is still relatively safe to purchase. A prudent chemist will most likely stock up on this chemical because the eventuality of more intense scrutiny is inevitable. The best way to make this product is to start with NaBH4 which is much more safe to buy. However, the way to go about making this catalyst is not very safe unless strict adherence to safety is used.

The 'cyano' part of cyanoborohydride is going to come from cyanide of course, and cyanide is lethal. Cyanide has no odor and will kill you instantly if a single whiff of it is inhaled. Everything must be done in a hood and study or investigation of the literature beyond what is published here is strongly urged. To acquire a stabilized source of cyanide one is going to need to introduce hydrogen cyanide (HCN) into tetrahydrofuran (THF) solvent. Ideally one would want to use a cannister of cyanide gas and bubble it into the THF but Strike seriously doubts such a thing will be sold to a street punk. This is because such an item, in the wrong hands, could be a terrible terrorist weapon. The best way a home chemist could 'safely' produce HCN is by generating it herself.

To make a cyanide/THF solution one is going to have to create HCN from sodium or potassium cyanide. To do this one is going to need to use the apparatus seen in fig. 14. There are going to be some minor changes though. The reaction flask is not going to be a simple single-neck flask but, instead, is going to be a single-neck with a sidearm inlet tube or a three neck flask with one of the necks stoppered and the other one plugged with a rubber stopper that has a wide glass tube extending all the way from the outside of the flask down to the bottom of the flask. At the other end of the apparatus is the vacuum adapter connected to the re

ceiving flask. If one were to look up into the vacuum adapter one will see that it has a little drip tube that extends down its neck where liquids normally drips from into the receiving flask. Right? Now, what one wants to do is attach an extension of tubing or glass to the end of that drip tube so that it will extend all the way to the bottom of the receiving flask. The chemist does this because she wants the cyanide to bubble through the THF that she is going to place in the receiving flask. The receiving flask itself must be sitting in a an ice bath.

In professional laboratories, scientists use things called gas dispersion tubes at the ends of their 'drip tubes'. These kinds of 'drip tubes' are commercially made pieces of glass that have a tip made out of porous ceramic. When a gas Is pulled through the end of a gas disperser it is busted up into a bunch of tiny, fizzy bubbles which greatly enhances the absorption of the HCN gas into the solvent. What the chemist has is a bubbling tip that is going to produce big bubbles. This works, but not as efficiently. The best way a chemist can approximate a phase separator is by wrapping a bunch of netting or some such shit around the tip. But one should simply buy the proper gas dispersion tube from any glassware maker.

To make the HCN/THF the chemist is going to have the setup as described in place, under the hood and the vent from the vacuum source must be channeled way, way outside (the vacuum is not on at this point mind you). In the preweighed receiving flask is placed a 300g of THF. In the reaction flask is placed 113g sodium cyanide (NaCN) and 500mL water and the stoppers are immediately put back in place. The vacuum hose, which is connected to the vacuum adapter is going to have a hose clamp on it so that vacuum flow can be regulated. With the hose pinched shut by the clamp, the vacuum is turned on and the flow is slowly started by adjusting the clamp. What the chemist wants to see is a slow bubbling coming from the inlet tube in the reaction flask and also from the bubbling tube in the receiving flask. The vacuum flow should not be any stronger than what is needed to cause this -282 -

bubbling. The solution in the reaction flask should be stirrinq during all this so that the NaCN dissolves into the water No HCN gas should be evolving at this point.

To release the HCN gas one is going to acidify the solution with concentrated H2S04. To do this one is going to gradually add 30mL of H2S04 through the inlet tube. Each addition aliquot will cause the bubbling to temporarily stop, which is normal. The pull of the vacuum will get things going again. After addition the solution is brought to a boil and kept there for 1 hour. The chemist can now remove the receiving flask, weigh it and hope that it has gained approximately 60g in weight. That gain in weight will be due to the absorption of HCN.

With the HCN solution in hand, the rest of the procedure goes pretty quickly. 80g NaBH3 in 1L THF is stirred at 25°C and then the HCN/THF solution is gradually added. Bubbling caused by the release of hydrogen will occur (no smoking!) as the solution stirs for 1 hour at 25°C. The solution is then heated at reflux until no more hydrogen can be seen evolving. The solution is then vacuum filtered and the filtrate removed of THF by vacuum distillation to give NaBH3CN (91%). Whew! All catalysts, including this one, must be stored immediately so that they have no prolonged exposure to air and moisture. This is especially true for NaBH3CN.

The following is the current list of DEA List I and List II chemicals. List I chemicals can only be bought or owned if one has a DEA or state permit. List II chemicals can be purchased in any amount below the given threshold. If one requires an amount of List II chemical above the threshold amount, then will need the same DEA permit for List I chemicals.

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