Without knowing about the subject, why Turkey never entered the fray during the Napoleonic wars?
It is true that they fought against the Russians around 1800's, but as far as I know, the engagement was on individual disputes between Russia and Turkey.
It seems strange that one of the main (although sick) empires never participated in the major battles of the Napoleonic wars. It is also weird that they neither gave material support to one of the parties, as was England's case.