Full Idea
Brentano's thesis is that all mental phenomena are intentional i.e. representational. Support for this view is that assimilating phenomenal experience to attitudes we explain the essential unity of the mind.
Gist of Idea
Mental unity suggests that qualia and intentionality must connect
Source
report of Franz Brentano (Psychology from an empirical standpoint [1874]) by Georges Rey - Contemporary Philosophy of Mind 11.5
Book Reference
Rey,Georges: 'Contemporary Philosophy of Mind' [Blackwell 1997], p.301
A Reaction
Unifying intentionality and qualia in a single theory looks like a good move, but which one has priority? Evolutionary theory says priority goes to whatever produces behaviour. My intuition is that qualia are more basic - in tiny insects, say.