I am going to try to prepare some P2NP from benzaldehyde and nitroethane following this procedure:
The aldehyde (5g), 5 ml. of the nitroalkane, and 2g of ammonium acetate were added to 20 ml of glacial acetic acid. The resulting solution was refluxed for two hours and then poured into ice water. If a solid product was obtained it was collected and recrystallized from methanol, ethanol, or acetic acid. If the product was an oil it was separated and crystallized, if possible, from one of the above solvents.
However, I got a bottle of reagent-grade ammonium acetate from a chem supplier and it is very wet. To be fair, they never marketed it as anhydrous, though.
Does that matter when I'm not using a dean-stark trap? If so, how much will it affect the yield, and is there a way accessible for a hobby chemist to dry it?
What hydration state it is in - like is it trihydrate? This is important in order to calculate the amount needed. I guess 2g of anhydrous is needed in the procedure.
Update: 10g Benzaldehyde was poured into 50ml Sodium bicarbonate water solution, stirred, and left to settle down for 30 min or so.
3.5g of very wet ammonium acetate was measured - it was foolishly assumed the salt is trihydrate and calculated that 2g salt is present in 3.4g trihydrate. However, that was left for 30 minutes in the open as an experiment and picked up another 500mg of water, so this calculation is more or less incorrect. Some of the water can be removed by pressing against something like toilet paper btw.
20g of GAA was added to a 500 ml RBF. The acetate was added to the acid and shaken for a few minutes until fully dissolved. 5.5ml Nitroethane and 5ml from the washed Benzaldehyde were added.
This was refluxed for 2 hours with the condenser hardly needed at all. After that, the heat was stopped and the hot solution was poured into 150ml ice-cold water. No crystallization occurred whatsoever. The organic layer was picked up with a syringe and was 5ml of thick deep-yellow oil weighing 5.87g and with a PH of approx. 7. This was put in the fridge for two hours but no crystallization occurred, just a hint of some cloudiness like in this photo: 
(not as much, though), probably contained some P2NP but frustratingly little, and was not worth the efforts.
This was poured in 50ml of ice-cold IPA for fun and it partially dissolved but was poured down the drain.
Obviously, a dean-stark apparatus is needed to monitor when water evolution will stop so the reaction is complete, and to get a reasonable yield.
My question is - what is in that yellow organic layer? Unreacted benzaldehyde and some P2NP, right? So, how can those be separated easily and efficiently? I read somewhere that this can be washed with sodium bicarbonate solution but I don't see why.
