Бромирование 4′-метилпропиофенона в 2-бром-4'-метилпропиофенон. Крупный масштаб.
I would like to ask,After 12 h precipitate is formed.Sodium bicarbonate aq solution is added to the reaction mixture to reach neutral pH 6-7, stir it well.What concentration of sodium bicarbonate solution should I use?
Or add water first and then slowly add sodium bicarbonate to make the pH value of the flushing water solution reach 6-7
Or add water first and then slowly add sodium bicarbonate to make the pH value of the flushing water solution reach 6-7
To clean acidic crystals, a 1% to 2% sodium bicarbonate aqueous solution can usually be used. The concentration of sodium bicarbonate can also be adjusted according to the specific situation of the acidic crystals. For example, highly acidic crystals may require a more concentrated sodium bicarbonate solution.
Specifically:
Generally acidic crystals: 1% to 2% sodium bicarbonate aqueous solution is a more commonly used concentration, which can effectively neutralize the acidity and avoid damaging the crystals.
Highly acidic crystals: The concentration of sodium bicarbonate can be appropriately increased, such as 3% or 4% solution.
Special cases: If the crystals are also sensitive to weak alkaline solutions, consider using a lower sodium bicarbonate concentration, or use other weak alkaline solutions.
Other precautions:
Solubility:
Sodium bicarbonate has limited solubility in water. Generally speaking, a concentration of 1% to 2% is already relatively easy to dissolve.
Operation:
When cleaning, you can first immerse the crystals in a sodium bicarbonate aqueous solution, and then gently wipe them with a soft brush or cotton cloth.
Rinse:
After washing, you need to rinse with pure water to remove the residual sodium bicarbonate solution.
In general, it is a common and safe practice to use 1% to 2% sodium bicarbonate aqueous solution to clean acid crystals. If you encounter special circumstances, you need to adjust the concentration according to the specific situation.
Can I follow this method?
Specifically:
Generally acidic crystals: 1% to 2% sodium bicarbonate aqueous solution is a more commonly used concentration, which can effectively neutralize the acidity and avoid damaging the crystals.
Highly acidic crystals: The concentration of sodium bicarbonate can be appropriately increased, such as 3% or 4% solution.
Special cases: If the crystals are also sensitive to weak alkaline solutions, consider using a lower sodium bicarbonate concentration, or use other weak alkaline solutions.
Other precautions:
Solubility:
Sodium bicarbonate has limited solubility in water. Generally speaking, a concentration of 1% to 2% is already relatively easy to dissolve.
Operation:
When cleaning, you can first immerse the crystals in a sodium bicarbonate aqueous solution, and then gently wipe them with a soft brush or cotton cloth.
Rinse:
After washing, you need to rinse with pure water to remove the residual sodium bicarbonate solution.
In general, it is a common and safe practice to use 1% to 2% sodium bicarbonate aqueous solution to clean acid crystals. If you encounter special circumstances, you need to adjust the concentration according to the specific situation.
Can I follow this method?
fuckk man just made some 2b4m today and this shit is hell of a irritant (My carelessness for trying to air drying before reading the safety sheet) but dude my lab now reeks of this and after 9 hours there is still mild irritation to eyes and skin when entering into lab.
And for some reason yields are moderate not as high as texts say, although this was my first time doing this so i did mess up somewhere for now its probably the addition of H2O2 i think i stopped bit too early believing that most of the ketone is brominated and further bromine is not being consumed.
And for some reason yields are moderate not as high as texts say, although this was my first time doing this so i did mess up somewhere for now its probably the addition of H2O2 i think i stopped bit too early believing that most of the ketone is brominated and further bromine is not being consumed.