You have it backwards. Even though our image of the brain and all of the concepts associated with the semantic shortcut "brain" are mental fabrications, the mind itself is the product of a terribly complex arrangement of quarks which happen to exist within the physical boundaries that we conventionally call a brain.
That the mind exists within physical boundaries, (ie, quantitative material, temporal, or spatial relationships) has not been demonstrated.
I did a search about property dualism and I couldn't see much written here on this site.