Doubly N-Methylated Porphyrinoids

Area of Science:

• Organic Chemistry
• Supramolecular Chemistry
• Materials Science

Background:

• Porphyrins and corroles are aromatic π-electronic macrocycles with significant applications.
• Controlling the three-dimensional structure of macrocycles is crucial for tuning their properties.

Purpose of the Study:

• To synthesize doubly inner N-methylated porphyrins and corroles.
• To investigate the structural consequences of N-methylation.
• To explore the resulting chiroptical properties.

Main Methods:

• Multistep and one-pot synthesis reactions for N-methylation.
• Single-crystal synchrotron X-ray diffraction for structural determination.
• Optical resolution techniques.

Main Results:

• Successfully synthesized doubly N-methylated porphyrin and corrole derivatives.
• X-ray analysis confirmed the presence of two N-methyl groups on neighboring pyrrole rings in up/down conformations.
• Induced distorted geometries in the macrocyclic structures.
• Achieved optical resolution, leading to observable chiroptical properties.

Conclusions:

• Doubly inner N-methylation is an effective strategy to introduce chirality into porphyrin and corrole macrocycles.
• The distorted geometries resulting from N-substitution are key to inducing chiroptical activity.
• This work provides a pathway for designing novel chiral macrocyclic materials.