JefferyH
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Would some alkyl amines have the same properties as ammonia?
I'm trying to find an alternative to using liquid ammonia for reactions. Liquid ammonia being used to dissolve various ionic salts. Would I get a
similar functionality if I used one of the propylamine derivatives, like isopropylamine, diisopropylamine, or propylamine? Or would these not be able
to have the same ionic dissolving power that ammonia has?
If possible I would want to use something like Triethylamine since it lacks free hydrogen, but I'm not sure of its polar properties in comparison to
ammonia.
I assumed this would be intuitive since they are all polar, but I haven't found any papers using alkyl amines in place of liquid ammonia.
[Edited on 13-9-2014 by JefferyH]
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deltaH
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You may want to consider using ethylenediamine or formamide.
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JefferyH
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I forgot to mention I still plan to be cooling the reaction mix to well into negative celcius, so those two are out of the question.
Triethylamine seems like it may be optimal since it doesn't have nitrogenous free hydrogen.... Do you think this would inhibit its ability to dissolve
ionics?
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deltaH
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Alkyl groups larger than methyl significantly reduce the polarity of these liquids AFAIK. Speculatively, I don't think you will get joy from
triethylamine or higher alkylamine.
The details you provide are scant, but you may want to consider polyethers. Glymes, such as dimethoxyethane (DME), are powerful coordinating aprotic
solvents. Crown ethers are even more so (though costly) and will handle alkali salts for you.
Propylene carbonate (PC) is a VERY polar aprotic solvent that has a low melting point (-49C).
You may also experiment with solutions of solvents, for example, a mix of a coordinating ether like DME and PC. Such combos are often used in lithium
batteries, though I think they usually use ethylene carbonate... but 'same difference' 
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JefferyH
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I will consider those. I need to consider if a solvent can survive very strong reaction conditions (very electrophilic or nucleophilic environment).
In spite of ammonias nucleophilicity, it tolerates quite well in some electrophilic environments. dimethxyoxyethane could work. I will have to do some
research into that.
I'm going to go on the search for a list of polar aprotic solvents.... if you have a link you might can recommend
[Edited on 14-9-2014 by JefferyH]
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macckone
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No single solvent is going to be as versatile as liquid ammonia.
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DraconicAcid
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Quote: Originally posted by JefferyH  | I'm trying to find an alternative to using liquid ammonia for reactions. Liquid ammonia being used to dissolve various ionic salts. Would I get a
similar functionality if I used one of the propylamine derivatives, like isopropylamine, diisopropylamine, or propylamine? Or would these not be able
to have the same ionic dissolving power that ammonia has?
If possible I would want to use something like Triethylamine since it lacks free hydrogen, but I'm not sure of its polar properties in comparison to
ammonia.
I assumed this would be intuitive since they are all polar, but I haven't found any papers using alkyl amines in place of liquid ammonia.
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Ask yourself- does isopropanol have the same solvent properties as water? If not, why not? How about diethyl ether?
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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