[Nekromantis]

Hi,

In my research I get ionic liquids. Now i must do N-methylpyrrolidine from pvrrolidine and methyl iodide. But i have a small problem. Methyl iodide is very reactive. In reaction with triethylamine formed some kind of ionic liquid so this is bad method even in -10 celcius degrees. Second method whose i made is with 50% NaOH. After extraction ethyl acetate GC analysis showed product and small amount methyl iodide. Boiling point ethyl acetate and N-methylpyrrolidine are close. How to split product from ethyl acetate? Column chromatography? Maybe distillation? I'm afraid, that amine will decomposed. In the low pressure distillation product may exit together with ethyl acetate. Someone has an idea how to separate them?

Sorry for my english

[pgk]

Add methanol (b.p.= 65°C) that forms an azeotrope with ethyl acetate at 62°C and distill under normal pressure, by hoping that no ternary azeotrope with N-methylpyrrolidine will be formed (though, not probable because methanol does not form azeotrope with water). When the distillation temperature raises above 62-63°C, then apply the vacuum distillation. Although, N-methylpyrrolidine is rather stable at the boiling temperature.
Do not distil under reduced pressure because the distillation range will be narrowed.
You cannot use water because it forms an azeotrope with ethyl acetate at 70 °C and with N-methylpyrrolidine at 72°C (US Patent  4,892,959). Besides, a ternary azeotrope system is quite possible.
https://en.wikipedia.org/wiki/Azeotrope_%28data%29
Please, note that extractive separation of N-methylpyrrolidine is also described in the cited patent US 4,892,959.

[Nekromantis]

Thanks for help me:)
I will try make a PTC reaction use solid K2CO3. I will use toluene as a solvent and more pyrrolidine. N-methylpyrrolidine have boiling point 80-81 and pyrrolidine 87. So I will hope that product will leave reaction mixture first. Or second option I will use CH2Cl2 and evaporate in first step solvent.

[pgk]

Do not thank me, due to a terrible mistake in my replying post. The correct is:
When the distillation temperature rases above 65-66°C and after cooling at room temperature, then you apply the vacuum distillation by gradually increasing the temperature (otherwise, everything will instantly pass into the other side).
In preference, do not distil under reduced pressure because the distillation range will be narrowed.
Please, note also that polar solvents (e.g. CH2Cl2) favor polar reactions; while highly boiling point solvents (e.g. toluene) accelerate reactions by thermodynamic control.
Good luck.