# Piperonal to MDP2NP (Methanol w/o Catalyst)



## Fenster (Oct 26, 2022)

Greetings,

This is my first post, I found this novel method and have not seen it shared much to date. This seems like a much easier route. 

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“15g of piperonal was dissolved in 40ml of methanol under stirring in a 250ml Erlenmeyer flask. When all of the piperonal had dissolved, 7.1g nitroethane was added to the solution. The flask was put in a ice/salt-bath with magnetic stirring, and when the temperature of the solution had dropped to 0°C, an ice-cold solution of 4g of NaOH in 20ml H2O was added at such a rate that the temperature never rose above 10°C. A white precipitate formed at the bottom of the flask during this addition, which was broken up with a glass rod. 

The stirring was continued for another hour, while the temperature of the solution was never allowed to rise above 5°C, and at the end of this time, 100 ml of ice-cold H2O was added to the solution, which caused even more precipitation of white solid. 

The whole slurry was poured into 100 ml of ice-cold 2M HCl solution in a 500ml Erlenmeyer flask, which was gently swirled, and there was a slight bubbling and fizzing, with the color of the solution shifting from white to blue to green to yellow in under a minute. Quite spectacular! When the fizzing had subsided, the solution was once again placed in in an ice-bath with magnetic stirring. 

When the temperature had dropped to about 5°C, the solution was clear with yellow granules of crude product at the bottom. The granules were filtered with suction, and recrystallized from IPA. After air-drying, the canary-yellow crystals amounted to a yield of 65-70% of theory.”

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My question to crowd source here- 
If one substitute the molecular equivalent weight of piperonal for benzaldehyde will I get P2NP? 

Methanol being very easy to source and no need for a catalyst. Seems in heavy basic conditions there is no need to add the catalyst when using Piperonal + Nitroethane in methanol. Once acidifying the RM crystals seem to crash out without much more effort. There are several advantages if this route works for other aldehydes.


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## Fenster

Tried this today with Benzaldehyde as a possible route to P2NP. 

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22mls of chilled Bza was dissolved in 80ml of methanol in an ice bath. 15ml of Nitroethane was added and stirring commenced. 8g if NaOH in 40ml was added slowly to control the temperature below 5 degrees. The solution tuned a strong yellow colour.

No sign of white precipitate yet. Will see what happens. Will continue stirring for 60mins then dump 200ml H20. Then Acidify and see what happens.

After 60mins 200ml of ice cold h20 was added which appeared to make a white precipitate. The whole solution was dumped into 200ml of ice cold 2M HCL solution. Some fizzing occured and temp rose to 16. Nothing more happening. After cooling to below 5 solution remained yellow and no obvious crystals. Will filter, see what's left and then leave solution in the freezer.

A few white specs remained. The Rx mixture never cleared. Stayed the texture of orange juice. 

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The only questionable reactant was the Nitroethane as I have not distilled. It does produce a white flame, something I've seen only from nitro ethane or methane.


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## UWe9o12jkied91d

I personally haven't seen this "route" before, but you may be misunderstanding something.This synthesis does, in fact , use a catalyst, the base.Some things that are not primary amines work, like the soda or secondary amines but they dont work well and you need a ton of time to leave it to react.The reaction between nitroethane and benzaldehyde takes place even with just the 2 mixed together, but is highly reversible and takes a lot of time and heat.Secondly I don't get the point of cooling to 5 C? This reaction needs heat to be driven, as far as I know, regardless of solvent used it's the same reaction after all, in this case at least, but I may bee mistaken.
Any reason not to just use a primary amine + AcOH?


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## Fenster

I actually tried this with GABA as the catalyst as well


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