Furch
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Prep. of EtNO2 using acetone as solv.
I wonder if the standard solvents for the preparation of nitroethane from ethyl bromide and NaNO2 can be swapped for other Sn2 facilitating solvents,
such as acetone. The reason is that acetone for most people is much cheaper and more readily available than DMSO and DMF and formamide.
Since the reaction in question takes place at room temperature, the low boiling point of acetone can hardly be a reason for it not to work.
I know acetone isn't AS good a Sn2 promoting solvent as DMF and DMSO and formamide, but perhaps it's worth the compromise?
What am I missing?
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guy
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The problem is that acetone doesn't dissolve ionic salts like NaNO2 well. DMF and DSMO are very polar and can dissolve those compounds.
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Furch
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Sure, my common sense tells me that as well... But I also understand that for instance NaI in acetone reacts readily with other alkylhalides... This
wouldn't be possible unless the I- dissolves to some extent in the acetone. So reasonably it should have some solvative effect on inorganic salts, no?
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guy
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Then I guess in the cases where it does dissolve and doesn't react with the acetone it should work.
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jon
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yeah there was some procedure where hypothetically it was done in DMSO but ethyl bromide would make a sulfur ylide with dmso so we know that's
bullshit.
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chemrox
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Jon, if the ethyl bromide is distilled from DMSO the product will be acetaldehyde...there's a paper on this I shall find and send you or post if
requested.
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Nicodem
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Quote: | Originally posted by Furch
Sure, my common sense tells me that as well... But I also understand that for instance NaI in acetone reacts readily with other alkylhalides... This
wouldn't be possible unless the I- dissolves to some extent in the acetone. So reasonably it should have some solvative effect on inorganic salts, no?
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But NaNO2 (unlike NaI) is insoluble in acetone, at least as far as I know.
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
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