Modular enantioselective photocatalysts from privileged pybox scaffolds
Summary
Modern organic synthesis relies upon the availability of chiral catalysts to control the stereochemistry of bond-forming reactions. Several families of chiral catalysts have become recognized as "privileged" structures because of their notable generality for diverse transformations with different reaction mechanisms. However, examples of highly enantioselective photocatalyst structures remain scarce. We have designed a family of enantioselective photocatalysts by modifying the structures o
Content
# Modular enantioselective photocatalysts from privileged pybox scaffolds
*Published: 2026 Apr 9*
Modern organic synthesis relies upon the availability of chiral catalysts to
control the stereochemistry of bond-forming reactions. Several families of
chiral catalysts have become recognized as "privileged" structures because of
their notable generality for diverse transformations with different reaction
mechanisms. However, examples of highly enantioselective photocatalyst
structures remain scarce. We have designed a family of enantioselective
photocatalysts by modifying the structures of privileged pyridine bis(oxazoline)
complexes with electron-donating carbazole units. The chiral ligands are
accessible through a three-step synthetic sequence starting from commercially
available chiral pool materials, and their charge-transfer photochemistry can be
rationally tuned to optimize photocatalytic activity. We demonstrate the
generality of these new chiral photocatalyst structures in a series of three
model asymmetric reactions, which includes both photoredox and excited-state
photoreactions.
DOI: 10.1126/science.aeb5832