This npc is no longer available in game.
This boss had also been the only source for the non-soulbound version of Recipe: Flask of Supreme Power. Your alchemist will need to be exalted with the Keepers of Time to purchase the BoP version ( Recipe: Flask of Supreme Power) that was added in The Burning Crusade.
Ras Frostwhisper was one of the original bosses of Scholomance prior to Mists of Pandaria.
It's a real shame that he didn't make the cut. The lich was an interesting boss fight and I loved his emotes. Also, The Laboratory (his room) was one of the few places in the game where an Alchemist could find an alchemy lab. Alchemy labs - until Patch 3.0.8 - were necessary in the creation of several potent flasks.
For a historical list of the lich's loot table, see Ras Frostwhisper.