Porphyrins: Synthesis, Geometry, Stability, H-H Intramolecular coupling constant, Aromaticity, and Intramolecular hydrogen bonding

Porphyrins are relevant examples of macrocycles compounds, also known as annulenes with 18-πelectron systems [1], that have obtained significant attention because of their vital role in biologicalprocesses, such as photosynthesis (chlorophyll and bacteriochlorophyll), oxygen transportation, andoxygen activation (heme) [2-4].meso-Substituted trans-porphyrinderivativies are crucialbuilding blocks inporphyrin-based biomimetic systemsand molecular materials and can be used forthe construction of welldefinedporphyrin-based architectures.As part of an ongoing project, meso-substituted porphyrins bearingspecific patterns of substituents were synthesized and characterized by 1H NMR, 13C NMR, 1H-1H COSY,and MALDI-ToF mass spectra. Also, a modification of the Adler method for THPP (meso-tetrakis(4-hydroxyphenyl)porphyrin) and a purification method for TAPP (meso-tetrakis(4-aminophenyl) porphyrin)were reported. Furthermore, theoretical calculationssuch as H-H Intramolecular coupling constant,Intramolecular hydrogen bonding, and aromaticitywere performed to determine effects of various factorson stability of the porphyrins. Results of computed total spin-spin coupling constants and correspondingcomponents were considered to connect stability of porphyrin derivatives to the obtained data.

کلیدواژه ها:

Porphyrin ، Density functional calculations ، Stability ، H-H Intramolecular coupling constant ، Aromaticity