Macrocyclic core size limit for stabilizing ferrocenoporphyrinoids.

Incorporation of 1,1'-substitued ferrocene into the macrocyclic π-conjugation pathways of corrole and subporphyrin leads to unprecedented rupture of the ferrocene unit with structural isolation of a dicyclopentadiene bridged porphyrinoid and a 1,3,4 trichloro-6a,6b,9,9a,10,10a-hexahydro-6H-6,10 methanopentaleno[1,2-c] chromen-2-ol-bridged porphyrinoid, respectively, both of which lack global macrocyclic π-conjugation.