How to properly work with potassium HMDS
If you would look up the properties of KHMDS from a chemical supplier, you will find it will react violently with with water. So do keep it under inert atmosphere.

As for solubility, it is a non-nucleophilic base, so probable no substitution and addition like reactions will occur. I wont suspect it will be a problem there.

A comment on the use though. If you plan to use this, explore the dangers and possibilities of a substance like this a bit further than asking it here. For safety considerations. Look up the MSDS sheets from your supplier and be sure to only use this in a properly equipped lab. 

Hope this helped.