[zsinger]

All,
Attempting to make a N-acyl-2 substituted aziridine.  I am going through the azido-alcohol intermediate (Styrene Oxide reacted with sodium azide, ammonium chloride in a 3/1 (MeOH/H2O) system.  However, I am having a HELL of a time finding a good elution system to attain a good Rf to separate the azido alcohol from the Styrene oxide impurities.  Any suggestions.  I have tried basically ALL Hex:EtOAc systems.  In a university lab, so have access to anything imaginable.
       -Zack

[phth]

Are you doing gradient with column? Try to shoot for 33%, aka 0.33Rf, up the TLC plate for the spots you want and use that solvent system.  Other than that reverse phase silica may work better. 

[Dan]

I have tried basically ALL Hex:EtOAc systems.  In a university lab, so have access to anything imaginable.

Well, you've only tried one solvent combination really. Try acetone/hexane and ether/hexane for starters. Switching the aliphatic hydrocarbon for toluene can very, very helpful.

A non-exhaustive list:

Possible strong solvents: Alcohols, MeCN, THF, Acetone, EtOAc, ether, DCM, chloroform
Possible weak solvents: Hexanes, toluene, DCM, chloroform

Try combinations of different strong and weak solvents.