Synthesis and characterization of iron N-confused porphyrins: Structural evidences of agostic interaction

The iron complexes of N-confused porphyrin, Fe- Ph Ph (NCTPP)Br and Fe(NCTPP)(SC7H7), are synthesized. The solid-state structures show nonplanar geometries with an inverted pyrrole ring tilted away from the porphyrin plane The bond distances between iron and inner-core C-H for Fe(NCTPP)Br are in the range of N an agostic interaction, while the corresponding distances for Fe(NCTPP)(SC7H7) are slightly longer. These complexes demonstrate potential intermediates prior to the formation of planar NCTPP complexes.