Synthesis of Highly Electron-Deficient Iron(II)-Porphyrins and Their Catalytic Efficiency for C─N Bond Formation...

Herein, we report the synthesis and characterization of highly electron-deficient, air-stable iron(II)porphyrin complex (1) [Fe^II(TFPPCl₈)(OHMe)₂, H₂TFPPCl₈ = tetrakis(pentafluorophenyl)-2,3,7,8,12,13,17,18-octachloroporphyrin, OHMe = methanol] and its catalytic activity toward olefin aziridination. The addition of highly electron-withdrawing substituents at meso and β-positions on the periphery of the porphyrin macrocycle significantly distorts its geometric structure, and this modulation impacts its macrocycle properties while enabling the facile isolation of air-stable high-spin Fe(TFPPCl₈)(OHMe)₂ in a highly nonplanar macrocyclic environment. The complex is structurally analyzed through single-crystal X-ray diffraction, and the supramolecular self-assembly was investigated using density functional theory (DFT) and Hirshfeld analysis. Hirshfeld's study reveals the formation of halogen-bonded supramolecular synthons involving fluorine and chlorine atoms on the porphyrin periphery. Catalytic aziridination on olefins was performed under mild conditions, showing that the catalyst is highly active toward aziridine formation under homogeneous conditions. The presence of strong electron-withdrawing substituents (F and Cl) at the porphyrin periphery makes the metal center highly electron-deficient and have high electron affinity, leading to variation in activity for substituted olefins. DFT calculations were performed to investigate the electronic structure of the (Por)Fe^IVNTs species, which is an active site during catalysis reaction.