- Language
- 🇺🇸
- Joined
- Dec 18, 2022
- Messages
- 52
- Reaction score
- 26
- Points
- 18
@ImOutAlso
I do exactly like you said in step 1, first water, then IPA, turn on stirring, make sure it is going nicely and then add all NaBH4. Temp rise is +1-2C.
I did see your setup, quite nice, I was also impressed by the equipment choice you described, definitely wish I had went the more budget route also.
The next time I finish salting out, I will vacuum filter off the IPA in the buchner and after stripping 99% of IPA, I will pour acetone on the moist cake, give it a stir and turn the vacuum on again, correct?
As for the color, I had read about oxidation of this compound years ago and your description confirmed it for me, it was in fact just oxidation
@UWe9o12jkied91d
Thank you as well, next time I will try cooling with cold water when it reaches 50C, I now believe I previously overcooled and way too early too, not letting the reaction reach the needed temperature. I add cucl2 dropwise dissolved in the least amount of water possible after adding the rest of P2NP and letting it stir for a minute or two.
When I apply the heat at 80C for 30 minutes, I am left with two layers, clear on top and blackish copper with nabh4 it seems like on bottom, but the reaction seems to still be going (bubbling) even after stirring is turned off and temperature is allowed to fall down to about 40C. I tried to solve this by heating for longer (50 minutes, it stopped refluxing at this point), but quite strong bubbling still persisted.
I read about this method and some people have mentioned this can be caused by unreacted NABH4 which is apparently added in excess in this synthesis, I believe they described adding acetic acid to "neutralize" the NABH4 and stop the mixture from bubbling, is this something that should be considered at all? Or is it fine if I run the reaction mixture through a vacuum filtration at 30-40C to get rid of boro and copper then proceed to base it with cold NaOH? I don't see any borate crystals forming when separating the layers, so I should be good, right?
I do exactly like you said in step 1, first water, then IPA, turn on stirring, make sure it is going nicely and then add all NaBH4. Temp rise is +1-2C.
I did see your setup, quite nice, I was also impressed by the equipment choice you described, definitely wish I had went the more budget route also.
The next time I finish salting out, I will vacuum filter off the IPA in the buchner and after stripping 99% of IPA, I will pour acetone on the moist cake, give it a stir and turn the vacuum on again, correct?
As for the color, I had read about oxidation of this compound years ago and your description confirmed it for me, it was in fact just oxidation
@UWe9o12jkied91d
Thank you as well, next time I will try cooling with cold water when it reaches 50C, I now believe I previously overcooled and way too early too, not letting the reaction reach the needed temperature. I add cucl2 dropwise dissolved in the least amount of water possible after adding the rest of P2NP and letting it stir for a minute or two.
When I apply the heat at 80C for 30 minutes, I am left with two layers, clear on top and blackish copper with nabh4 it seems like on bottom, but the reaction seems to still be going (bubbling) even after stirring is turned off and temperature is allowed to fall down to about 40C. I tried to solve this by heating for longer (50 minutes, it stopped refluxing at this point), but quite strong bubbling still persisted.
I read about this method and some people have mentioned this can be caused by unreacted NABH4 which is apparently added in excess in this synthesis, I believe they described adding acetic acid to "neutralize" the NABH4 and stop the mixture from bubbling, is this something that should be considered at all? Or is it fine if I run the reaction mixture through a vacuum filtration at 30-40C to get rid of boro and copper then proceed to base it with cold NaOH? I don't see any borate crystals forming when separating the layers, so I should be good, right?
- Joined
- May 21, 2022
- Messages
- 229
- Reaction score
- 207
- Points
- 43
- Deals
- 3
- By WinterDust
Yes,
When you wash with acetone, you don't need to stir, just keep the vacuum on and pour the acetone directly.
When you wash with acetone, you don't need to stir, just keep the vacuum on and pour the acetone directly.