Журнал "Макрогетероциклы"

Timothy D. Lash^@

Department of Chemistry, Illinois State University, Normal, Illinois 61790-4160, U.S.A.

^@ E-mail: tdlash@ilstu.edu

Macrogeterocycles, 2008 1(1) 9-20

Diverse carbaporphyrinoid systems have been synthesized using ‘3 + 1’ MacDonald condensations, Lindsey-Rothemund reactions and other strategies. In common with the N-confused porphyrins (NCPs), these compounds have a CNNN core that can facilitate the generation of organometallic derivatives. Benzocarbaporphyrins and tropiporphyrins, with indene or cycloheptatriene units in place of a pyrrole ring, readily form silver(III) complexes and some gold(III) derivatives have also been prepared. On the other hand, benziporphyrins and azuliporphyrins, which have a benzene or azulene unit in place of a pyrrole moiety, are dianionic ligands that afford NiII, PdII and PtII complexes. Stable iridium and rhodium derivatives of azuliporphyrins can also be generated. 2-Methyl or 2-phenyl NCPs act as dianionic ligands forming NiII and PdII complexes but reactions with silver(I) acetate gave the aromatic 3-oxoNCP silver(III) derivatives. A related N-phenylpyrazole-containing porphyrinoid gave nickel(II) and palladium(II) complexes but these showed little or no aromatic character. Oxybenziporphyrins, which have a semiquinone subunit, can form PdII, PtII, CuIII, AgIII and AuIII derivatives and can therefore act as both dianionic and a trianionic ligands. Finally, a diazuliporphyrin has been used to prepare the first example of a palladium(II) dicarbaporphyrinoid complex. These investigations demonstrate that the unique characteristics of organometallic compounds derived from carbaporphyrins and related porphyrin analogues are starting to rival the significance of the better known metal complexes of N-confused porphyrins.