Supramolecular Engineering and Self-Assembly Strategies in Photoredox Catalysis

Visible-light-mediated photoredox catalysis has evolved as an efficient and mild alternative to conventional organic synthesis. Inspired by the elegance and sophistication of natural photosynthetic machinery involving complex self-assembled systems, recently researchers have resorted to the implementation of supramolecular chemistry in photoredox catalytic processes with the objective of achieving improved efficiency for known chemical reactions, as well as developing advanced methodologies for inaccessible transformations. Supramolecular engineering offers the ability to customize the existing properties of traditional photoredox catalysts by various self-assembly strategies and expands their scope in cutting-edge synthetic methodologies by means of their noncovalent interactions with different chemical components. In this review, we summarize the recent advances and key achievements in photoredox catalytic synthesis adopting various supramolecular techniques based on organic self-assembled systems and underline their advantages and mechanistic facets. Diverse directional noncovalent interaction driven photoredox catalytic systems are thoroughly discussed. Furthermore, self-assembly strategies for various photocatalytic reactions within confined nanospaces (viz. micelles, vesicles, polymersomes, polymeric nanoparticles, gels etc.) are summarized. Finally, a brief perspective on the encouraging future prospects and challenges in this contemporary field of supramolecular photoredox catalysis is presented.