1-Phenyl-2-nitropropene (P2NP) Video Synthesis From Benzaldehyde and Nitroethane. Henry Reaction.

[Manisj@1290]

I Successfully synthesized nitroethane but not pure can I make p2np with impure nitroethane.

 

[HIGGS BOSSON]

Depends on how dirty your nitroethane is. Try putting a few grams in the microwave as an experiment.

 

[wael gano]

This is an effort and a small amount of experience. You can modify some things

 

[wael gano]

Add 215ml absolute ethanol
Add 108 ml (2 moles) of sulfuric acid slowly after the addition is complete. Heat to 80 degrees for 2.5 hours.
Turn off the heat and cool the mixture
Place it in a plate, then take 200 grams of sodium carbonate and add it until it equals the pH 8
After that, wait hours for the sodium carbonate to react well. Without adding water, there is a little ethanol. Allow it to evaporate into the air
The yield is 290 grams
Mixed moles of sodium ethyl sulfate
Mole of sodium sulfate
I used 2 moles of sulfuric acid, producing one mole of ethyl sulfate
One mole of sulfuric acid remains unreacted
Sodium sulfate, it doesn't matter, don't separate anything. Put everything and add 1 mole of sodium nitrite 103 grams with 50 ml of water and start distillation.

 

[wael gano]

Add 215ml absolute ethanol
Add 108 ml (2 moles) of sulfuric acid slowly after the addition is complete. Heat to 80 degrees for 2.5 hours.
Turn off the heat and cool the mixture
Place it in a plate, then take 200 grams of sodium carbonate and add it until it equals the pH 8
After that, wait hours for the sodium carbonate to react well. Without adding water, there is a little ethanol. Allow it to evaporate into the air
The yield is 290 grams
Mixed moles of sodium ethyl sulfate
Mole of sodium sulfate
I used 2 moles of sulfuric acid, producing one mole of ethyl sulfate
One mole of sulfuric acid remains unreacted
Sodium sulfate, it doesn't matter, don't separate anything. Put everything and add 1 mole of sodium nitrite 103 grams with 50 ml of water and start distillation.

 

[Manisj@1290]

What will I receive after distallation??

 

[wael gano]

Did you understand what I wrote to you?

 

[Manisj@1290]

I don't know about this new method, so I am a little confused because you are using neither calcium carbonate nor potassium carbonate. Will you please explain in detail so that I do not face any problem in synthesizing this method?

 

[wael gano]

This reaction has some manipulation. I will tell you why I do not use calcium carbonate in my experience
Because calcium carbonate is used to isolate sodium ethyl sulphate, in the end, he makes calcium carbonate to neutralize the unreacted sulfuric acid and makes it insoluble calcium sulphate, then he puts water to keep the calcium ethyl sulphate in the water, then perform an exchange reaction by adding sodium carbonate and keep the sodium ethyl sulphate in the water. You need Evaporation of water and upon heating sodium ethyl sulphate decomposes and results in loss of yield

 

[wael gano]

Therefore, I exclude the use of water and calcium carbonate. I do not want to heat the crystals, as they may decompose
Adding sodium carbonate and neutralizing the remaining sulfuric acid produces sodium sulfate as an impurity. Its presence in the distillation of nitroethane does not affect the reaction, but with this work you can skip the step of evaporating the water so that the sodium ethyl sulfate does not decompose.
The second question: Why did I not use potassium carbonate?
Added sodium carbonate, both of which act as a catalyst for nitroethane
Do this method and you will get a better nitroethane yield and save some time, such as filtration, fumigation, and purification, because your main goal is to obtain nitroethane and nothing else.
As I told you, sodium sulfate is an inert impurity that does not affect nitrite. In the end, when weighing the crystals, only half of the crystals are sodium ethyl sulfate.

 

[Manisj@1290]

Ok I understand and thank you for getting this method.

 

[handle]

Has anyone else attempted this method?

 

[wael gano]

Yes, a tried and tested method

 

[Donotdon't]

Can I use methylamine instead of butylamine?

 

[HIGGS BOSSON]

In theory, it is possible, but personally I had a bad synthesis

 

[rampage]

Hi
Not sure if this is the right section but does anyone know if this recipe will work?

Preparation of phenylnitropropanol:
Into a suitable beaker or conical flask place 51mls of benzaldehyde, followed by 33mls of nitroethane,
immediately thereafter add in 30 mls of a 30% potassium carbonate solution, rapidly stir the entire
mixture at room temperature for 2 hrs.
A cold water bath or ice bath may be needed to keep the reaction mixture at ambient temperature
(room temperature) or below. Do not allow the reaction mixture to get above 25 degrees celsius.
After stirring for 2 hrs add to the reaction mixture 200mls of diethyl ether, shortly thereafter add in
90mls of a 10% sodium bisulfite solution and moderately stir the entire reaction mixture for 30 minutes.
Afterwards place the entire reaction mixture into a seperatory funnel and remove the lower aqueous
layer, leave the ether layer in the seperatory funnel and wash the ether layer with 3 x 75ml portions of
cold water, each time removing the lower aqueous layer.
Place the ether layer into a suitable beaker or conical flask and add 15gms of anhydrous magnesium
sulfate and stir the entire mixture for 10 minutes to absorb any water in the ether. Then filter off the
magnesium sulfate.
Place the filtered ether mixture into a distallation apparatus and remove the ether, when no more ether
passes over or is collected allow the residue to cool to room temperature, then collect this residue as it
consists of the desired phenylnitropropanol.

 

[TheCook]

This method should work, but you must bear in mind that it does not result in P2NP.
Phenylnitropropanol is a β-nitroalcohol that contains a hydroxy group (-OH) on the carbon atom next to the nitro group (-NO2). The general structural formula is C6H5CH(OH)CH2NO2.
P2NP (1-phenyl-2-nitropropene) is a nitroalkene that can be produced by dehydration (splitting off water) of phenylnitropropanol or directly by condensation of benzaldehyde with nitroethane under certain conditions that promote the formation of the double bond. The structural formula is C6H5CH=CHNO2.

What do you need phenylnitropropanol for?

 

[handle]

The Nitroalkene can be reduced with Fe and HCl. >Here<

 

[BongMan]

reduction with Fe and Hcl creepy and not good for large scale use instead Tin(II)chloride it is easier and feasible on both lab and large scale.

 

[rampage]

heres the suppossed summary of this recipe, not sure if its correct, if it doesnt result in ephedrine what does it result in?
Summary:

In this process, ephedrine is prepared by the condensation of benzaldehyde with nitroethane in the
presence of potassium carbonate, then the mixture is treated with ether and then a solution of sodium
bisulfite which removes any unreacted benzaldehyde, the ether layer is recovered, washed and then
dried and the resulting ether mixture then evaporated to recover the intermediate product,
phenylnitropropanol.
This phenylnitropropanol is then reduced by reacting it with formaldehyde in the presence of acetic acid
and zinc dust. After the reduction the reaction mixture is treated with hydrogen sulfide gas to
precipitate any dissolved zinc, the resulting mixture is then filtered and treated with ether followed by
hydrochloric acid. The ether layer is then removed and the aqueous layer is then treated with sodium
carbonate to liberate the freebase of ephedrine. The freebase is then extracted into ether, the ether
layer is then recovered and dried, then evaporated or treated with hydrogen chloride gas to obtain the
hydrochloride.

 

[waltjr5858]

Is there any issue at all using Nitroethane that has possible traces of Ethel formate and possibly Ethel acetate along with it? Very small amounts....

 

[BongMan]

well you can use it with small trace although it is solvent and not interfere much in reaction but may be affect little on yields

 

[waltjr5858]

That's fine if the yield suffers a little bit... thanks.