Spirodiporphyrins - As binuclear metal complexes

Figures of eight correlate with corrolates: The surprising formation of the spirodicorrole dinickel complex 1, the first spirodiporphyrin as a metal complex, is the result of the varied chemistry of the "figure-eight" cyclooctapyrrole octaphyrin-(1.1.1.0.1.1.1.0). The conversion of the cyclooctapyrrole into 1 is brought about by a sequence of oxidation and a nickel(II) acetate induced cascade of rearrangement reactions. In structural respects, 1 stands out because of the orthogonal arrangement of the two nickelcorrolate chromophores linked through a common spiro carbon atom.