I know this thread is old but I figured why start a new one when my post is specifically related...

Upon reducing for the second time (as stated above), some crystals began to form.  I then removed the rest of the solution to evaporate. 

However the crystals which gathered after the noted reduction appear to fumaric acid, whereas the crystals from the first bit of the clean up and the final evaporation appear to be DMT fumarate (both by smell and appearance. 

It would make sense to me that after the reduction the less soluble F.A would precipitate first but could someone confirm or deny this?

Thanks,

T