If you're looking for a solution to a typical undergrad OC problem, then it looks as though it's been answered. In practicality, however, there are more ways to get passed the emulsion. Filter the mixture through a bed of celite in a fritted glass filter, or use ultrasound.
On a very large scale (1 kg), solvent removal and replacement with a less problematic solvent can work.
If you're looking for a solution to a typical undergrad OC problem, then it looks as though it's been answered. In practicality, however, there are more ways to get passed the emulsion. Filter the mixture through a bed of celite in a fritted glass filter, or use ultrasound.
On a very large scale (1 kg), solvent removal and replacement with a less problematic solvent can work.
If you're looking for a solution to a typical undergrad OC problem, then it looks as though it's been answered. In practicality, however, there are more ways to get passed the emulsion. Filter the mixture through a bed of celite in a fritted glass filter, or use ultrasound.
On a very large scale (1 kg), solvent removal and replacement with a less problematic solvent can work.
Cheers!
Filtering approach agreed, I personally use silica gel though.
Solvent removal approach agreed, this is why some procedure mentioned to remove the reaction solvent such as MeOH and THF before extraction
Ultrasonic approach.....it looks it is doing the opposite (it encourages the formation of emulsion, see https://www.hielscher.com/emulsify_01.htm)
If you're looking for a solution to a typical undergrad OC problem, then it looks as though it's been answered. In practicality, however, there are more ways to get passed the emulsion. Filter the mixture through a bed of celite in a fritted glass filter, or use ultrasound.
On a very large scale (1 kg), solvent removal and replacement with a less problematic solvent can work.
Cheers!
Filtering approach agreed, I personally use silica gel though.
Solvent removal approach agreed, this is why some procedure mentioned to remove the reaction solvent such as MeOH and THF before extraction
Ultrasonic approach.....it looks it is doing the opposite (it encourages the formation of emulsion, see https://www.hielscher.com/emulsify_01.htm)
If you're looking for a solution to a typical undergrad OC problem, then it looks as though it's been answered. In practicality, however, there are more ways to get passed the emulsion. Filter the mixture through a bed of celite in a fritted glass filter, or use ultrasound.
On a very large scale (1 kg), solvent removal and replacement with a less problematic solvent can work.
Cheers!
Filtering approach agreed, I personally use silica gel though.
Solvent removal approach agreed, this is why some procedure mentioned to remove the reaction solvent such as MeOH and THF before extraction
Ultrasonic approach.....it looks it is doing the opposite (it encourages the formation of emulsion, see https://www.hielscher.com/emulsify_01.htm)
Kamilu, I think the ultrasound approach is an example of "too little... too much". I can get some emulsions to dissipate in an ultrasound bath by sitting for 15 min. The immersion probes are far too powerful. Quite literally, I could not get a Takai reaction to go thermally, nor with ultrasound bath, but the reaction was over in 30 minutes with an ultrasound immersion probe. Your picture looks like the standard "cell disruptor" or immersion probe.
I agree, ultrasound is not better than the other two methods.
If you're looking for a solution to a typical undergrad OC problem, then it looks as though it's been answered. In practicality, however, there are more ways to get passed the emulsion. Filter the mixture through a bed of celite in a fritted glass filter, or use ultrasound.
On a very large scale (1 kg), solvent removal and replacement with a less problematic solvent can work.
Cheers!
Filtering approach agreed, I personally use silica gel though.
Solvent removal approach agreed, this is why some procedure mentioned to remove the reaction solvent such as MeOH and THF before extraction
Ultrasonic approach.....it looks it is doing the opposite (it encourages the formation of emulsion, see https://www.hielscher.com/emulsify_01.htm)
Kamilu, I think the ultrasound approach is an example of "too little... too much". I can get some emulsions to dissipate in an ultrasound bath by sitting for 15 min. The immersion probes are far too powerful. Quite literally, I could not get a Takai reaction to go thermally, nor with ultrasound bath, but the reaction was over in 30 minutes with an ultrasound immersion probe. Your picture looks like the standard "cell disruptor" or immersion probe.
I agree, ultrasound is not better than the other two methods.
Well, in fact, the ethanol case is something contradictory to what I have actually experienced in the lab.
When there is something that mixes very well both with water and organic, emulsion occurs.
Therefore, when the separating funnel contains THF, DMF etc, phase separation is not very good.
I am not sure if the ethanol case is the same here, though
yes it is. Methanol is less of a problem, for example, it will phase separate if diluted in 1/2 with water(acid, base, etc) and extraction with organic solvent such as DCM, EtOAc, Et2O....from personal experience. Ethanol is a different story.
Well, in fact, the ethanol case is something contradictory to what I have actually experienced in the lab.
When there is something that mixes very well both with water and organic, emulsion occurs.
Therefore, when the separating funnel contains THF, DMF etc, phase separation is not very good.
I am not sure if the ethanol case is the same here, though
yes it is. Methanol is less of a problem, for example, it will phase separate if diluted in 1/2 with water(acid, base, etc) and extraction with organic solvent such as DCM, EtOAc, Et2O....from personal experience. Ethanol is a different story.
On a very large scale (1 kg), solvent removal and replacement with a less problematic solvent can work.
Cheers!
On a very large scale (1 kg), solvent removal and replacement with a less problematic solvent can work.
Cheers!
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VOTE
Filtering approach agreed, I personally use silica gel though.
Solvent removal approach agreed, this is why some procedure mentioned to remove the reaction solvent such as MeOH and THF before extraction
Ultrasonic approach.....it looks it is doing the opposite (it encourages the formation of emulsion, see https://www.hielscher.com/emulsify_01.htm)
Filtering approach agreed, I personally use silica gel though.
Solvent removal approach agreed, this is why some procedure mentioned to remove the reaction solvent such as MeOH and THF before extraction
Ultrasonic approach.....it looks it is doing the opposite (it encourages the formation of emulsion, see https://www.hielscher.com/emulsify_01.htm)
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VOTE
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VOTE
When there is something that mixes very well both with water and organic, emulsion occurs.
Therefore, when the separating funnel contains THF, DMF etc, phase separation is not very good.
I am not sure if the ethanol case is the same here, though
When there is something that mixes very well both with water and organic, emulsion occurs.
Therefore, when the separating funnel contains THF, DMF etc, phase separation is not very good.
I am not sure if the ethanol case is the same here, though
More
VOTE
Kamilu, I think the ultrasound approach is an example of "too little... too much". I can get some emulsions to dissipate in an ultrasound bath by sitting for 15 min. The immersion probes are far too powerful. Quite literally, I could not get a Takai reaction to go thermally, nor with ultrasound bath, but the reaction was over in 30 minutes with an ultrasound immersion probe. Your picture looks like the standard "cell disruptor" or immersion probe.
I agree, ultrasound is not better than the other two methods.
Kamilu, I think the ultrasound approach is an example of "too little... too much". I can get some emulsions to dissipate in an ultrasound bath by sitting for 15 min. The immersion probes are far too powerful. Quite literally, I could not get a Takai reaction to go thermally, nor with ultrasound bath, but the reaction was over in 30 minutes with an ultrasound immersion probe. Your picture looks like the standard "cell disruptor" or immersion probe.
I agree, ultrasound is not better than the other two methods.
More
VOTE
yes it is. Methanol is less of a problem, for example, it will phase separate if diluted in 1/2 with water(acid, base, etc) and extraction with organic solvent such as DCM, EtOAc, Et2O....from personal experience. Ethanol is a different story.
yes it is. Methanol is less of a problem, for example, it will phase separate if diluted in 1/2 with water(acid, base, etc) and extraction with organic solvent such as DCM, EtOAc, Et2O....from personal experience. Ethanol is a different story.
More
VOTE