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Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: Shannon Dove on January 08, 2019, 02:55:56 PM

Title: Random made chemicals
Post by: Shannon Dove on January 08, 2019, 02:55:56 PM
If you take a simple compound like methanol and subject it to various forms of energy, such as ultrasound, ultraviolet, infared, high voltage low amperage DC electricity, high amperage low voltage high frequency ac electricity, etc, etc...what kind of molecules would form? Is there a limit to the complexity or is it possible that most any could form?  If you add aquas ammonium, could protein form, could alkaloids form?
Title: Re: Random made chemicals
Post by: Borek on January 08, 2019, 07:13:44 PM
Sounds a bit like https://en.wikipedia.org/wiki/Miller–Urey_experiment

Technically there is no limit to the complexity of the molecules that can be produced, but the more complex ones have very low probability of being produced and of surviving in harsh conditions of the experiment, so in practice you wouldn't see anything too complicated.
Title: Re: Random made chemicals
Post by: Shannon Dove on January 08, 2019, 11:27:15 PM
Yes, that Miller Urey experiment is exactly what I am thinking about.
Does anyone think this is worthy of more intense research? What about as part of the dial a molecule project?  Let's say you need chemicals A B and C as precursors, so you run the liquid from the reaction chamber through a thin tube with analytical equipment such as spectrometers, when it recognizes one of the precursors, that portion is diverted to a separate container, and the rest is pumped back into the reaction chamber, and this process is repeated for hours or even months. When you have enough of chemicals A,B, and C, you run them through a chromatography column
Title: Re: Random made chemicals
Post by: wildfyr on January 09, 2019, 12:02:12 AM
This type of experiments always produce a whole complex mess of products that are difficult to separate in meaningful amounts. The method you described for purification contains a grain of truth but in reality purification is a much much more complicated process.

They are an active topic of research but not for trying to synthesize particular chemicals but rather study the origins of life.
Title: Re: Random made chemicals
Post by: Enthalpy on January 09, 2019, 12:27:05 PM
Reproducing the Miller-Urey experiment may be fun but it would improbably bring new science. They obtained amino-acids, you would too. But before obtaining a living cell, you would need a full ocean and half a billion years - if it really proceeded like this.

The "analytical part" of your proposal needs more thoughts. "When the equipment recognizes a precursor" seems to suggest recognizing individual molecules, and even patience wouldn't make any macroscopic amount from molecules. Also, most analysis equipment destroys the molecules to recognize them. You have to restrict to some processes like chromatography.

You might want to consider my old proposal to make micro-sorters by semiconductor technology. I meant them to separate sick blood cells, they could separate individual molecules in amounts less tiny than otherwise. Integrate 104 actuators per chip, put 106 chips in a machine, let them operate in 10-2s over 107s, and you have processed 1019 elements, of which you keep some. Still not a mole, but already in the µg region. You need some distinctive molecular property that the actuators can recognize easily and quickly, like fluorescence.

In the same spirit as Miller-Urey, I'd like to suggest the random production of cage molecules, in amount sufficient to study their properties. Take a broad mix of alkenes, allenes, alkynes, polyenes... and inject atomic carbon among them, for instance by sublimation of carbon after diffusion through tantalum
https://en.wikipedia.org/wiki/Atomic_carbon
https://en.wikipedia.org/wiki/Phil_Shevlin
or by one of the untested methods (= risky lengthy) I suggested there
http://www.chemicalforums.com/index.php?topic=72951.0
Title: Re: Random made chemicals
Post by: Shannon Dove on January 13, 2019, 10:34:01 AM
I want your opinion about another scenario.
I used to be interested in energetic materials, so I thought of this: if you was to take animal matter such as earth worms, grind it up in water, then add various forms of energy, would a few glycerin nitrate molecules form? So with electricity, the anode would oxidize some of the proteins to form nitrates, the cathode would form hydroxides that might react with fats to form glycerin, and so on and so on.
Now please don't say how stupid this is,....this is actually very interesting to think of what chemicals might be randomly formed in the parts per trillion range, and this study might actually be applicable to other more interesting topics of chemistry
Title: Re: Random made chemicals
Post by: Borek on January 13, 2019, 11:29:05 AM
Just because some random molecule was made doesn't matter much by itself. What matters is whether the compound can be produced in substantial amounts and isolated. Otherwise it is just a curiosity without practical applications.
Title: Re: Random made chemicals
Post by: Shannon Dove on January 13, 2019, 01:01:09 PM
It does have practical applications.
For example, if you found a trace amount of glycerin nitrate in a soil sample, you might want to know if it's man made or if it occurred naturally. I can see a clever defense attorney using this research to claim that a trace amount of pethadine found in a container could have been randomly made from the conditions of the environment the container was in.
Title: Re: Random made chemicals
Post by: wildfyr on January 13, 2019, 03:54:54 PM
It's all a matter of concentration. We can detect picomolar concentrations if an assay is performed correctly and we know what we are looking for.

And I think such a defense attorney would have to put a little more oomph behind the mechanism of formation for it to stand up against another expert witness like an organic chemist. Things are not truly "randomly made." They need atomic feedstocks, energy, and often catalysts. Part of the problem with the Miller-Urey experiment is that only quite simple molecules are really made. Single amino acids and sugars. Something like like an known active drug molecule is so enormously unlikely. It's like arguing that according to quantum mechanics there is a statistical chance I could teleport to Hawaii right today.

Your earthworm experiment is of the same vein, I think ppt would be orders of magnitude too high a concentration for nitroglycerin from such an experiment unless it was carefully designed to produce such molecules. Try to think of this in real numbers from a statistical mechanics point of view. Almost anything is possible, but we need to try to work with what is likely. Occam's razor and all that.

Its why the origin of complex biomolecules and life on Earth is still a problem we struggle mightily with.

Title: Re: Random made chemicals
Post by: Enthalpy on January 13, 2019, 07:48:55 PM
Same opinion: a nitro is highly improbable, a trinitro even worse. Extreme detection sensitivity won't suffice. Amino acids were a smaller step away from the reactants used.

But finding an interesting molecule in a big bunch is sensible as a first step before synthesizing it in a practical way. Hence my suggestion with atomic carbon, made more interesting because the synthesis was very little researched and may very well produce molecules still never obtained.

Similarly, you could prepare a wide mix of Grignard reactants, synthesize at once tens of thousands of branched alkanes, and sort out the ones with a wide liquid range. At least the separation on temperature criteria is decently easy. Once you have some drops that stay liquid from -100°C to +180°C, you can apply the more subtle separation and analysis methods. Low-freezing non-flammable alkanes would have commercial applications. Even for pure science, as we can't predict a freezing point, knowing more atypical compounds would help.

Or you could check if the selectivity rules for some synthesis methods are well understood. Make a mix of tens of type A and type B reactants, with similar reactivity, apply something like Diels-Alder, or 2+2 photoaddition, or any one you prefer, and check if the many product abundances are distributed about as expected. From the surprises, you might amend the guidelines.
Title: Re: Random made chemicals
Post by: Shannon Dove on January 14, 2019, 10:12:43 AM
I appreciate everyone's response, thank you for taking the time to consider what many think to be a stupid subject.
I have another question for you all.... wouldn't organic molecules identified in space be considered "random made"?
Title: Re: Random made chemicals
Post by: pgk on January 14, 2019, 01:09:01 PM
Not exactly!
Under conditions like in the Miller’s experiment, in neonatal planets and space objects, formation of organic molecules could be considered as “random made”.
But their existence also depends on their stability to heat and UV irradiation, as well as on their chemical and physical properties.
As an indicative example, imagine the new-born planet Mars. Due to the intense volcanic activity, there was an initial atmosphere rich or “random made” methane and oxygen. Within time, oxygen combusts methane to CO2 and water. But Mars’ gravity is low and cannot hold the light gases, such as CH4 and H2O with molecular weight 16 and 18, respectively and which easily escaped with the help of solar wind. The remaining atmosphere of CO2 and O2 is not quite dense and cannot adequately filter UV irradiation, which catalyzes the reaction between oxygen and chloride salts. As a consequence, only gaseous CO2 and perchlorate salts are detected on Mars today, together with traces of oxygen and indications of traces of methane.   
PS: The above is a hypothetical scenario and not a detailed and "official" history of the Mars’ atmosphere. 
Title: Re: Random made chemicals
Post by: Enthalpy on January 14, 2019, 05:10:15 PM
wouldn't organic molecules identified in space be considered "random made"?
If you wish.

In vacuum, only tiny molecules and radicals have been observed, up to very few carbons. You won't recreate that abundance of radicals in a lab on Earth. Not quite interesting anyway.

On and in space rocks, the molecules aren't so exciting. The most intriguing lesson is that fragile molecules can survive in space if protected by a rock, which lets some astronomers propose that life may spread randomly from a planet to an other or from a solar system to an other through meteoritic impact. Which leaves a worry open: what diversity and what quantity of life is needed to colonize a sterile world?
Title: Re: Random made chemicals
Post by: pgk on January 15, 2019, 11:49:21 AM
CORRECTION:
….. such as CH4 and H2O with molecular mass 16 and 18, respectively…….
(Molecular weights 16 and 18 on Earth, correspond to ≈ 6 and ≈ 7 on Mars; where gravity is ≈ 0.38 g.)