Nonplanar porphyrins: synthesis, properties, and unique functionalities

Abstract

This review summarizes the chemistry of nonplanar porphyrins in terms of synthetic strategy, structural features governing their properties, unique functionalities derived from ring distortion, and further development of related research.

Clamshell Arrangements and Chirality in Cocrystals of C70 with MII(octaethylporphyrin) (M = Co or Zn)

“…This distortion of the porphyrin is best seen in the displacement plot shown in Figure , which allows a comparison of the central Co II (OEP) molecule of ( 1 ) to the other two Co II (OEP) molecules in that structure and to another cocrystal, C 70 ·Co II (OEP)·C 6 H 6 ·CHCl 3 , which has the more usual 1:1 C 70 /Co II (OEP) stoichiometry. The central Co II (OEP) molecule in ( 1 ) is twisted into a saddle shape, whereas the other Co II (OEP) molecules in that cocrystal display only very slight dome distortions. The distortion of the porphyrin and the disposition of the ethyl groups makes the Co II (OEP) chiral in this environment.…”

Electrocatalytic Hydrogen Evolution of Bent Bis(dipyrrin) Ni(II) Complexes

“…The major absorption bands of the three Ni­(II) complexes at 90–100 nm were red-shifted compared with that of the corresponding free bases, which is attributed to the small gap between the theoretical highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) of Ni­(II) complexes estimated by density functional theory (DFT) calculations (Figure S12). − The 2c shows weaker red-shifted absorption than the 2a and 2b ; the reason is the strong electron-withdrawing pentafluorophenyl groups at meso-positions. − , The DFT calculation of 2c demonstrates the smaller HOMO–LUMO gap than that of 2a and 2b (Figure S12).…”

“…9−14 The electrocatalytic HER capacity of nonplanar tetra-pyrrolic Ni(II) complexes remains unexplored. 15 Therefore, the synthesis and HER study of novel bent Ni(II) porphyrinoid [such as bis(dipyrrin)] complexes are meaningful and necessary to investigate structure-dependent electrocatalytic HER capability and develop an ideal electrocatalytic H 2 evolution catalyst, so much so that bent Ni(II) bis(dipyrrin) complexes would work as new ECO 2 RR and ORR catalysts.…”

“… In 2020, we attributed the catalytic HER behavior of planar Ni­(II) porphyrin(1.1.1.1) to its distinct steric effects . Moreover, the molecular structures of porphyrin(1.1.1.1) complexes have been shown to influence the HER activity. − The electrocatalytic HER capacity of nonplanar tetra-pyrrolic Ni­(II) complexes remains unexplored . Therefore, the synthesis and HER study of novel bent Ni­(II) porphyrinoid [such as bis­(dipyrrin)] complexes are meaningful and necessary to investigate structure-dependent electrocatalytic HER capability and develop an ideal electrocatalytic H 2 evolution catalyst, so much so that bent Ni­(II) bis­(dipyrrin) complexes would work as new ECO 2 RR and ORR catalysts.…”

Persistent microporosity of a non-planar porphyrinoid based on multiple supramolecular interactions for nanomechanical sensor applications

“…While the introduction of macrocyclic saddle or curved conformations of tetrapyrroles 26 has sometimes been found to lead to porous structures, 27,28 these are generally not persistent and have also not been so far observed for the saddle-shaped 'quinophyrin' systems 24 most closely analogous with 1-ox. Saddling of the macrocycle ought to improve the prospects for the formation of structural vacancies but 1-ox is subject to multiple interactions in the structure.…”