Cou
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Do I really need to dry every chemical for a grignard reaction, even if it's new in a bottle from a chemical supplier?
I might be lazy, but I don't want to go thru the effort of drying and distilling everything.
The diethyl ether I have is new from chemsavers, ACS grade 99%+ anhydrous. Do I really need to set up a benzophenone sodium ketyl still?
Ethyl formate is new. Magnesium is new. The only thing I would expect to dry is the alkyl halide that I make myself.
For my first grignard reaction I'm hoping to react 2 equivalents of 1-bromoheptane with ethyl formate to get pentadecan-8-ol.
[Edited on 7-25-2020 by Cou]
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Tsjerk
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You could throw in some sieves in every bottle, but it is probably not really necessary. Especially when the ether is sold as anhydrous it should be
fine.
The drier the better, but even if the Grignard doesn't start you could use a pinch of iodine or some short alkyl bromide to get it started. After that
the only thing water will do is lower the yield.
[Edited on 25-7-2020 by Tsjerk]
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karlos³
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You have an ultrasound device?
Because then it will be successfull even with less than thorough drying.
And you can simply seat the ether over NaOH or KOH for a month and then decant and distill and the stuff will be dry as fuck(ouch! not a literal fuck
of course, lube is your friend  ).
[Edited on 25-7-2020 by karlos³]
[Edited on 25-7-2020 by karlos³]
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j_sum1
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Chemplayer did a video experimenting with just how much water you can get away with in a Grignard. (Quite a bit.)
But if you are just learning then why not err on the safe side?
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zed
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Never had a problem with virgin ether. Recycled ether often requires drying. As in, lots of drying.
May contain a surprising amount of water.
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draculic acid69
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I have some sieves on the way for this exact reason.id recommend at least testing for water before trying an anhydrous reaction if u desire a
result.just bcoz it says anhydrous doesn't mean by the time u get it store it and go to use it it's still anhydrous.lots of ppl have stories about the
dry ether or thf turning out to not be that dry
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