Ni(II)
10-Phosphacorrole, a porphyrinoid containing phosphorus
at the meso position, was synthesized from a bis(α,α′-dibromodipyrrin)
Ni(II) complex and a phosphine anion via the palladium-catalyzed formation
of a C–C and two C–P bonds. The optoelectronic properties
of Ni(II) 10-phosphacorrole can be modulated effectively by oxidation
or coordination of a metal to the phosphorus center. While Ni(II)
10-phosphacorrole exhibits a distinctly aromatic character due to
the cyclic conjugation of 18 π-electrons, its oxide exhibited
weak antiaromaticity, which was confirmed experimentally and theoretically.