Synthesis of Isobutyl Nitrite (88.2% Yield) from Isobutyl Alcohol and Nitrous Acid formed in Situte

Isobutyl nitrite is a non-polar, highly flammable, volatile, solvent and vasodilator. For this reason it used in the treatment of cyanide poisoning. It has the chemical formula C4H9NO2 and is an ester between isobutyl alcohol and nitrous acid, It has a density of 0.87g/ml, a boiling point of 67C, and is slightly soluble in water; but generally forms a yellow, oily, organic layer on top of water.

Using this procedure, designed and performed by the author, a percent yield of 88.2% (33.6ml) can be reported. The product is a pale yellow hydrophobic liquid with a density of 0.85 grams per ml (+/- 0.15 grams) that had a faint smell of almonds (do not deeply inhale!).

It is prepared by the addition of aqueous alkali nitrite to a solution of isobutyl alcohol and concentrated hydrochloric acid. The solution is kept chilled by a ice bath. The isobutyl nitrite may be removed by either distillation (recommended) or decanting/pipetting the organic layer. Once collected it is dried and washed with bicarbonate and anhydrous magnesium sulfate.

procedure

40 ml Of 31.45% hydrochloric acid (0.3213 mols) is stirred in a flask of between 200 and 150 ml with 30 ml of 99% isobutyl alcohol. The flask is then placed in a ice bath above a magnetic stir and a thermometer added. In another container, a solution of sodium nitrite is prepared with 22.4 grams of the salt, of 99% purity, and 35 ml of distilled water. Both solutions are left to cool to 10C. Once cool, the nitrite solution is administered drop wise to the reaction flask with stirring. Upon addition a greenish-blue liquid briefly forms (presumably nitrous acid). This liquid quickly disperses. If oxides of nitrogen can be seen forming than the addition is being conducted too quickly. The temperature must be kept bellow or at 10C to prevent the loss of product. Before all the nitrite is added, a white sparkly layer will form bellow the top yellow layer. When about 90% of the nitrite solution is added this white layer will disappear and be replaced with an arctic blue-green layer, with the top organic layer remaining unchanged.

Note: This is white layer is thought to be composed of fine droplets of isobutyl alcohol in water. When all the alcohol has been reacted away the blue-green color is due to excess nitrous acid in solution.

The solution is left to stir for one hour. Do not reflux.

The top yellow organic layer was removed by pipette and added to a clean 250ml 24/40 rbf. Also to this flask is added 10g of sodium bicarbonate powder. The flask was set up for simple distillation with heat supplied by steaming the bottom of the flask. The solution is distilled to 90% completion. In total 28.3 ml of yellow hydrophobic distillate was collected.

Next the solution left after the reaction, after the organic layer was removed, was also distilled under the same conditions. From this 5.3 ml of distillate, with the same properties as described above, was collected. The product should be dried with anhydrous magnesium sulfate.

Conclusion and Discussion

In total 33.6 ml was collected. This represents a 88.2% yield (38 ml being the theoretical).

In the future the organic layer should not be collected and distilled separately. Instead the reaction should be conducted in a 250 ml rbf and once the reaction is finished a distillation apparatus constructed around it.

Enjoy your poppers

Quote: Originally posted by DavidJR

Enjoy your poppers

Quote: Originally posted by VSEPR_VOID

Quote: Originally posted by DavidJR   Enjoy your poppers No thanks. I do not plan on ingesting a volatile solvent similar to how most SM users do not huff their ether. One use for instance is removing grease from joints. Well you can use isopropyl nitrite is hydrolyzes too quickly and is difficult to store. It is also very easy to evaporate or boil away meaning it is wonderful for extracting hydrophobic substances.

Quote: Originally posted by Melgar

I did try to get a strong whiff of it once, after I researched it well enough to know that it wasn't very dangerous. It made me lightheaded and made my face flush, but didn't seem especially recreational. Maybe you have to be doing some weird sex act in order for it to work properly? In any case, I wasn't.

Quote: Originally posted by VSEPR_VOID

Do you have any more information on where you get your alkali cyanide OTC? What is your full formulation for treating cyanide poisoning with isobutyl nitrite?

Quote: Originally posted by Melgar

Quote: Originally posted by VSEPR_VOID   Do you have any more information on where you get your alkali cyanide OTC? What is your full formulation for treating cyanide poisoning with isobutyl nitrite? Alkali cyanides can be purchased from a jeweler's supply store in the diamond district of Manhattan, in NYC. They also sell nitric acid for $60/gallon, and a bunch of other fun stuff that's useful for precious metal chemistry. Although I haven't had to treat myself or anyone else for cyanide poisoning yet, I'd start by leaving the area where there's any cyanide gas present. (Note that this would probably not work for ingesting the stuff, but I'm operating under the assumption that I'm competent enough to avoid that route of administration.) Then open the bottle, hold one nostril closed, and inhale strongly through my nose several times. Alkali nitrites convert some of the hemoglobin in your blood into methemoglobin, which cyanide preferentially binds to. Cyanide works by binding to cytochrome oxidase, but will switch to binding to methemoglobin if any is present. This gives your body a wider window during which it can metabolize the cyanide and convert the methemoglobin back to regular hemoglobin. This all assumes that I can get myself to a cyanide-free area with normal oxygen levels and reduce physical activity enough to lower my need for oxygen. It also assumes I'd be able to notice the effects of cyanide poisoning. Granted, I have no experience doing this, and don't know how well it would work if I did, but it still seems prudent to have something that could work on hand. Incidentally, alkyl nitrites aren't supposed to have very long shelf lives. They're apparently both decomposed by acids and decompose into acids. However, storing them over sodium carbonate is supposed to help with this, so that's how I store mine.

Quote: Originally posted by j_sum1

[moderating] Back on topic, DavidJR. No one needs this. [/moderating]

Quote: Originally posted by VSEPR_VOID

Well you can use isopropyl nitrite is hydrolyzes too quickly and is difficult to store.

Quote: Originally posted by LearnedAmateur

Quote: Originally posted by VSEPR_VOID   Well you can use isopropyl nitrite is hydrolyzes too quickly and is difficult to store. Actually neither of those are huge issues, saying that from experience having made a couple of hundred mils in small batches. Isopropyl nitrite hydrolyses quite slowly when not in the presence of an acid, storing over a small amount of sodium carbonate solution helps. I used to store it in a small stoppered test tube within a bunged boiling tube and it lasts for several months with minimal degradation. Alternately, a glass reagent bottle with PFTE tape on the thread will store it nicely as well, so long as there is no gap for it to evaporate through.

Quote: Originally posted by Boffis

Alkyl nitrites are very usefull reagent in organic synthesis. For instance they react with reactive methylene groups in the presence of HCl gas or sometimes even a little conc hydrochloric acid and with reactive methyl group usually in the presence of a sodium alkoxide to yield oximes. Butyl nitrite for instance reacts with ethyl methyl ketone in the presence of a little HCl to give 2,3-butadione monoxime which is the starting material for the preparation of dimethylglyoxime etc (See Vogel, Textbook of Preparative Organic Chemistry, 3 edition). With acetophenone and sodium ethoxide you get phenylglyoxal-2-oxime (so called isonitrosoacetophenone).