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

[MadHatter]

Actually, scratch that! It's crystallized fine overnight. But there's this brown slurry around the yellow crystals and it definately smells bad.
I made another batch without any temperature fuckups (actually ,using a sous-vide heater stick is a perfect heating system for this synth! Keeps a perfect, circulated water bath at an exact temperature, just a tip.). Now the second batch consists almost solely of solid, perfect yellow crytals.

But for the bad batch: I want to clean it up properly. But finding solubility- or rather INSOLUBILTY data for P2NP is hard. Remind me @G.Patton @William Dampier etc, is P2NP insoluble in water? Apparently its perfectly soluble in both methanol and DCM.- how about non-polars? Like toluene? Could I wash it with that? What would the best clean-up procedure be?
Recrystallizing from IPA apart, I mean.

 

[G.Patton]

Phenyl-2-nitropropene

General information 1-Phenyl-2-nitropropene, or simply phenyl-2-nitropropene, or P2NP, as it is commonly referred to, is a chemical compound from the aromatic group of compounds, with the formula C9H9NO2. It is a light-yellow crystalline solid with a distinct smell. Phenyl-2-nitropropene is used...

bbgate.com

 

[MadHatter]

So here's the picture. Canary yellow crystals from perfect temperature control to the left, darker yellow ones to the right, from the run which went well over 110 C for quite some time.

Best cleanup now? Recrystallize from methanol or IPA?

 

[G.Patton]

Product can be recrystallized from hexane, methanol, ethanol, isopropanol

 

[MadHatter]

So I opted for recrystallization from methanol Colour difference is still s´there, but slightly less so. Itäs a bitch getting the methanol out of the crystals though, I've been tampering with vacuum drying all day.

But I have moved on to the reduction phase with NaBH4, now have a bottle of formylamphetamine in acetone over MgSO4 standing in the fridge for salting tomorrow. I jut need to get a clean, good salting acid, which I sadly don't have right now.

 

[Dreadnsalty]

I am getting 2 separate layers during reflux. One darker amber on top and a smaller layer that is a light yellow on bottom. This along with a white precipitate on bottom as well. Is this normal?

 

[UWe9o12jkied91d]

Layers mean water, is your GAA pure?
the white precipitate might be your product, does it dissolve on heating?

 

[Dreadnsalty]

Brand new bottle of GAA at 99.85% purity. RM does smell strongly of GAA though. I will check product dissolve as soon as it gets done crystalizing out (hopefully)

 

[BrownRiceSyrup]

This reaction generates water right? Is there a way to remove the water to drive the reaction? I remember i saw somewhere someone used toluene as a solvent and used a dean start to remove the water but heat goes up to the 86 or whatever the azeotrope is with toluene. Is there anything wrong with that idea? Would that increase yield maybe?

 

[G.Patton]

Hello, yes.

 

[Hank Schrader]

When we produced phenylnitropropene, we did not use heating.
Poured into a flask
nitroethane+benzaldehyde+catalyst was closed and left at room temperature.
The flask was shaken once a day. After 8 days, the solution was poured into water ... and propene crystals fell immediately to the bottom. The water was decanted and crystallized in alcohol.

If someone wants to get very high quality propene,
I will give you the technology below:

1 mole benzaldehyde
1,2 mole of nitroethane
+ 18ml n-butylamine

Put this in a glass bottle and close it.
Shake hard a couple of times a day.
After 8 days, open the bottle and pour 1 liter into a container of hot water.
Shake... drain the water, repeat the procedure with 500 ml of water.
Pour phenylnitropropene with alcohol and heat until completely dissolved and leave in the freezer.
Propene is obtained by this method practically without color.
The color is transparent yellow, the structure is like crystal methamphetamine.

According to my method, it will turn out ~ 135-140g

 

[BrownRiceSyrup]

im just curious how you get a mole of nitroethane... I just spent the weekend making my own bromoethane and currently doing several runs of that and sodium nitrite... Ill eventually get a mole put together lol

 

[Hank Schrader]

Many people used to have unlimited access to Nitroethane.
Nitroethane costs 16.5 euros per kg on wholesale purchases.

 

[Hank Schrader]

Stocks of nitroethane are always good.

 

[BrownRiceSyrup]

wowww... yea well im in USA so its harder for us here.... at least for me. Im making this for myself, Kind of a hobby project so im ok with making my own nitroethane. Though If i can make a decent enough product ill consider working my way up the ladder, why not....

Do people really buy amphetamine salts in large quantities? Is that profitable? Figure theyd all go for anything thats methylated and not just boring amphetamines.....

 

[Hank Schrader]

By selling Amphetamine you can earn by quantity and low price.
Methamphetamine is certainly a more profitable product.
From a chemical point of view, it makes no difference to me what to produce - as long as they pay.

 

[Akashic]

when shaking initial solution daily 8 days at room temp, will the capped flask need to be vented? and should the rv avoid light exposure? I imagined I would choose a large amber media bottle and store in cupboard before it’s time to wash/xtaled
thanks for sharing Id really like to try your method

 

[41Dxflatline]

My avatar is a large crystal from this method, magnified

 

[JustMe]

Can I replace Cyclohexylamine ?
Benzaldehyde 50 ml
Nitroethane 50 ml
Glacial acetic acid 20 ml
aqueous methylamine 10 ml

 

[G.Patton]

Hello, can you clarify your question please? What do you want to replace exactly?

 

[JustMe]

replace Cyclohexylamine to aqueous methylamine
add aqueous methylamine place Cyclohexylamine

 

[G.Patton]

I'm not sure that methylamine has enough Lewis-base potential.

 

[Hank Schrader]

The Synthesis of beta-Nitrostyrenes - [www.rhodium.ws]

 

[G.Patton]

Interesting, there is methanolic methylamine snl.
There are lower yields 52-55%. In addition, methylamine is harder to get than cyclohexylamine

 

[JustMe]

*My English is weak

see thes
[Phenyl-2-Nitropropene à la Barium: 1 mol benzaldehyde, 1.2 mol nitroethane and 15 mL diluted aqueous methylamine in 150 mL alcohol. Stirred and slightly heated for ca 4 hours. The reaction mixture is brought over into a beaker and cooled in the fridge (4°C). If precipitation doesn't commence at this point, water is poured in and the mixture put back in the fridge. The P2NP oil layer will slowly (or sometimes quickly) start forming a crystalline layer. If it doesn't, scratching the wall with e.g. a glass rod will help. If even this won't help, it means you probably fucked something up. The yields I have had using this "adaptation": 81%(i-PrOH), 79%(i-PrOH), 75% (EtOH) and 71% (EtOH) (yields calculated after crystallizing once; I store my crystals in the freezer and also recrystallize them prior to use).]

*i dont have Cyclohexylamine.

 

[JustMe]

Synthesis of Phenyl-2-Nitropropene - [www.rhodium.ws]

 

[G.Patton]

ok