PC-12 Captain reported encountering wake turbulence on final approach to BOS that resulted in an upset. Control was regained and the flight landed safely.

Narrative

The PIC acted as PF and the SIC acted as PM for this event.Final approach for the ILS 22L into BOS; cleared for the ILS at 3000 feet. We planned to capture the glide slope high outside the FAF in an effort to avoid any wake turbulence.A 'caution wake turbulence' was given by the Approach Controller as we were switched over to the Tower Controller. The Approach Controller had us speed restricted to 180; 170 and 160 KIAS just prior to the event.Before the glide slope captured; we entered a wake vortex; the aircraft banked uncommanded about 10 degrees to the left before instantaneously snapping to an uncommanded 20-30 degree bank to the right; the nose of the aircraft also pitched down about 3-5 degrees. The pilot flying immediately disconnected the autopilot and put in left aileron and pitch up inputs to return the aircraft to level flight. The event lasted about 3 seconds; and aircraft control was quickly regained. PF continued the approach high on the glide path and left of course to avoid any remaining wake. Tower was informed the PFs approach decisions after the event and a normal approach and landing was made without further incidents.Approach Controller spacing with traffic and wake categories was inappropriate