njl
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Posts: 609
Registered: 26-11-2019
Location: under the sycamore tree
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Mood: ambivalent
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Freestyle chem
I very much enjoy "freestyle" chemistry, just winging a procedure based on background knowledge. For example, I just tried to see if nitromethane
could condense with urea in a henry-type reaction (the complication being that the carbonyl might not be sufficiently electrophilic due to the
amines). So, I added 10 mL of nitromethane and 5 grams of urea to a test tube and got to shaking. It was immediately obvious that the urea would take
ages to dissolve, so I added about 2 mL of water. Although this may inhibit dehydration, I figured it was worth a try. More shaking, still nothing
noticeable. I realized that urea might not be basic enough to catalyze the reaction, so I added around 500 mg of ammonium acetate. At this point,
there was a lower aqueous layer and an upper nitromethane layer. However, after shaking with the ammonium acetate, a homogenous mixture was formed.
When shaken, the solution now foams slightly, although this could be air bubbles (it does however look different than normally shaken water, more like
a soft drink). Anyway, I didn't really expect anything from the reaction. I did come up with a possible reaction pathway if there was condensation,
where the formed nitro-enamine is hydrolyzed to something like nitro-acetamide. Anyway, I love doing small, cheap experiments like this and I want to
know if other people do this. Do you only try reactions with the scientific method in mind (ie taking notes and thoroughly experimenting)?
PS The solution is now slightly yellow so maybe something is happening after all.
[Edited on 1-5-2021 by njl]
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Johnny Cappone
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Registered: 10-12-2020
Location: Brazil
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Sometimes I do something like that, but only if there is scientific plausibility on the route I'm following. It's not exactly "freestyle". It is like
solving any other problem, you divide it into parts and solve each one separately according to the tools you have at hand, without following a
"script" on how to solve the whole problem in one move. However, I avoid to reacting compounds whose interactions I do not know about and which may
trigger unwanted side reactions.
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Jome
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Location: Soutwest sweden
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If I'm not using or adapting a known process, I'll set up a theory, then I try the reaction small scale. I "discovered" the reaction between Al and
NaOH that way at 13, and at 19 in the same manner my chromate mixture turned mysteriously blue when I used excess H2O2. Recently
I made iodine with KClO3 and NaI just to see if it was viable.
I loved those videos where chemplayer set up small scale procedures to test rumored reactions, and when they tried out the reactions
of such "unknown" compounds to figure out what they are.
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Bedlasky
International Hazard
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Registered: 15-4-2019
Location: Period 5, group 6
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I do it a lot. Huge part of my molybdenum a tungsten work is just based on "random" reactions. Not truly random, but something which make sense and I
want to test it. For example: thiocyanate is good ligand, so I wanted to see how looks complexes of Mo with thiocyanate in different oxidation states
(or check if they even exists). And I latter found formula. Or: how molybdate react with aluminium foil in HCl. I suspected metallic Mo, but this
reaction started my interest in molybdenum because reallity is much more complex (I obtained from this reaction several molybdenum species in low
oxidation states).
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