Chiral covalent organic frameworks: emerging standalone photocatalysts for asymmetric organic transformations

Synthetic chemists continue to face significant challenges in synthesis of organic molecules with precise control over absolute stereochemistry. In this review, we cover recent advances in enantioselective transformations enabled by chiral covalent organic frameworks (CCOFs) as standalone photocatalysts. These CCOFs integrate a photoactive unit and a chiral element into a single platform, in which the photocatalytic component activates the substrates, while the chiral component directs stereo induction. Although researchers have so far limited synthetic applications to a small set of benchmark C-C bond formation reactions and oxidation processes, the scope of these transformations is expected to expand steadily in the near future. Inter-disciplinary knowledge transfer from asymmetric catalysis is driving this growth and is also enabling the extension of these materials into broader applications, including chiral separation, asymmetric electrocatalysis for organic synthesis and chiral sensing technologies.