tablet forming material

Hi there,
I'm currently looking for a material to form tablets which should have the
following properties:

*) the material should dissolve Tosylchloride, but not react with this
compound
*) solid at room temperature and I mean real solid, not like a gel or a wax
*) melting point above 50°C and below 100°C
*) soluble in 70%water 30% Acetonitrile
*) pH neutral

These are a lot of restrictions and the compounds we tested so far have
failed in one or more points, so if anybody has an idea, I would be
thankful.
Klaus G.