LONGECITY

I have two vacuum chambers, a five-gallon chamber and a one-gallon unit, which I use primarily for storing bulk tianeptine and desiccant packs. This method works extremely well. I’ve been able to store bulk tianeptine for an indefinite period of time with no degradation or clumping of the substance whatsoever. However, somebody pointed out to me that by storing some chemicals under vacuum, I may be altering their molecular structure by boiling off volatiles which are an integral part of the molecule. So are there any compounds which I absolutely should not be storing under vacuum?