UC235 - 2011-02-28
Hydrazine sulfate is prepared from readily available chemicals using the Hofmann rearrangement. Workup of the product is designed to prevent exposure to toxic hydrazine fumes, an important consideration for the amateur experimenter lacking a fume hood. The mechanism of the Hofmann rearrangement is also discussed.
@hkparker Feel free to. I'd appreciate it a lot! I should have more good stuff coming up soonish, not making any guarantees on time.
@NurdRage I already did, just not in video form. I guess I could add add a link in ye olde hydrazine thread.
Very impressive amount of yield! Thought it would be about 30 %
@NurdRage I have no idea. I'm so readily sidetracked with various syntheses. I have a benzamide reaction mixture that still needs to be worked up and some 6-methylquinoline that I've been avoiding doing anything with for months. It's occupying one of my 500ml RB flasks under water. I think I will do a dehydration of phthalic acid to phthalic anhydride as a video soon and once I've made some nitric acid, I have everything I need to get to luminol in short order.
Aldol condensation products.
@vmelkon I don't know. In fact, I recently discovered that the company (Kleanstrip) producing the only MEK I can find in my area has discontinued the product. I went out and searched hardware stores for any remaining cans. I could only find a gallon can that was kind of beaten up. I bought it anyway, and it was fortunately discounted significantly. Also very nice is that the replacement product is pure ethyl acetate.
Great explanation, bravo.
that yellow liquid could have a bit of ketazine
@UC235 Ok ill get on it, I'm going to do another sub4science video soon so it will be in there. Im glad your making videos, most channels on youtube dont go into as much detail as yours.
@acidum984 2) Hypochlorite in excess destroys hydrazine and lowers the yield. In fact, hypochlorite destroys a good portion of the hydrazine anyway, which is why the yield is about 50% and not more like 90%. The use of urea slows the formation of hydrazine relative to the Raschig process and improves yield. Here is an example of the Raschig process: bit(dot)ly/dRJvAG Notice only 35-37% yield 3) Urea is used in excess to minimize 2, and yield should be calculated from the limiting reagent.
@g3ov4n12 Because the impurities may be insoluble in absolute ethanol and if they precipitate and get caught on the product, what good does washing it do for me? Hydrazine sulfate is not that soluble in ice water so I'm not losing much. That's how washing works, generally. You trade a little yield for improved purity.
@acidum984 Hey, At the beginning ,he said that one could use domestic source of hypochlorite, however, one can not know for how long it has been on the shelves and it may have started degrading.
@UC235 Gotcha, i've been sitting on making sulfuric acid by the electrocatalyst process for almost a year. So i understand how life gets in the way. what kind of reductant are you planning to use? or have you not decided? I went with a dissolving metal reduction, but the yield is horrible and the wastage high.
Could you also do a video on the suzuki catalyitic process?
@UC235 ah interesting. I can't acquire either of those chemicals domestically, one of the downsides of being Canadian. I look forward to your results.
@NurdRage Well, I have a little bit of the preferred reductant which is sodium dithionite. It's also the bulk of a commercial product called super iron out and I suspect the reduction can be carried out directly with this product. Alternately, I have thiourea dioxide (thiox), a potent and readily available reducing agent used for small scale indigo dyeing. I suspect that the latter is more than suited for the final reduction.
Excellent! Now, some questions... 1) Could one use bleach as a domestic source of hipochlorite? 2) Why don't You use excess of hipochlorite, since it can easily degrade? 3) Why do You calculate yield to hipochlorite and not to urea, which is far stabile?
@acidum984 Yes, bleach can be used. However, a higher concentration is preferred to reduce solution volume. If only 5-6% is available, then you could add NaCl to it to so that it's almost saturated and the solubility of the organic phase later on is minimized. If you can only get even more dilute solutions (I believe this to be the case in parts of europe, you'd be better off making your own. Using the 12.5% that I prepared, the solution is just about saturated already and no excess is needed.
You rule.
@UC235 yeah the video is great, and i'm sure everyone would appreciate the detail and time that you put into it. I'm really impressed. You're going to be making luminol with all of this? when do you think that will be ready? I filmed my luminol approach but editing the video is taking forever.
I didn't hear this mentioned in your video but sodium hypochlorite is sensitive to degradation by light. Maybe store your solution or run your reaction in amber glassware. You might get a slightly better yield.
Why isn't there any MEK in Canadian hw stores?
Why didnt you used absolute ethanol to rinse? Since hydrazine sulfate is insoluble in it.
I have made hydrazine also by mixing H2O2 and ammonia in a stainless steel mug. I believe the mug had nickel in it which serves as a catalyst. Now you're probably wonering how i new it was hydrazine right? I knew it was hydrazine because when mixed with Cu(II)SO4 it formed a dark brown ppt instead of a dark blue Cu(II) amine complex. I think the dark brown ppt was copper reduced out of solution. Good vid.
Why does it turn orange when you add H2SO4. Did you say allyl condensation?
NurdRage - 2011-02-28
nice work, post it on sciencemadness!