Non-planar oligoarylene macrocycles from biphenyl.

Area of Science:

• Organic Chemistry
• Supramolecular Chemistry
• Photochemistry

Background:

• Macrocyclic chemistry explores the synthesis and properties of large ring structures.
• Perkin condensation and oxidative photocyclization are key reactions in organic synthesis.
• Designing molecules with specific three-dimensional architectures is crucial for advanced materials and molecular devices.

Purpose of the Study:

• To synthesize novel saddle-shaped and propeller-shaped macrocycles.
• To investigate the structural and geometric properties of these macrocycles.
• To explore the utility of Perkin condensations and photocyclizations in macrocycle synthesis.

Main Methods:

• Fourfold Perkin condensations of bis(phenylglyoxylic acid) derivatives with bis(phenylacetic acid) derivatives under transient high dilution.
• Subsequent four-fold oxidative photocyclizations to form the macrocyclic structures.
• Structural characterization using spectroscopic and crystallographic techniques (implied).

Main Results:

• Successful synthesis of saddle-shaped tetraphenanthrylene macrocycles.
• Successful synthesis of propeller-shaped double [5]helicene macrocycles.
• The saddle-shaped macrocycle exhibits an angle close to 90° between phenanthrene planes, resembling an ideal saddle.
• The propeller-shaped macrocycle preserves the geometry of unsubstituted [5]helicene without significant distortions.

Conclusions:

• Perkin condensations and photocyclizations are effective methods for constructing complex macrocycles with defined shapes.
• The synthesized macrocycles possess unique three-dimensional structures with potential applications in molecular recognition or materials science.
• The study demonstrates control over macrocyclic architecture through strategic synthetic design.