ketadd - 17-3-2011 at 13:19
How do I go about researching a proper solvent system for purification of a specific substance or class of substances?
For example, I`d like to know what solvents are used to recrystallize Testosterone Enanthate which is a steroid? I`ve done some searchs and came
across aqueous methanol as a possibillity.
I guess what I`m asking is for some help finding information on how to figure out what solvents to use for specific compounds for recrystallization.
ScienceSquirrel - 17-3-2011 at 14:39
For most organic compounds the best way is to look at the literature that details their synthesis or if dealing with a new compound, compounds that
are similar to it.
Chemistry is an art as well as a science. An experienced chemist can tease out crystals using cooling, solvent layering, etc.
It was said that the old German chemists could seed a solution with the detritus that fell from their beards! 
White Yeti - 29-7-2011 at 06:12
Usually, you would look at how polar the molecule is in relation to familiar substances that have concrete dipole moments.