Abstract
Originally discovered via vapor-phase pyrolysis of p-xylene,1 [2.2]paracyclophanes (pCps) have garnered significant attention due to their unique three-dimensional architecture2 and inherent planar chirality.3 Despite their promising physicochemical properties, optically active pCps are still predominantly obtained through enantiomer separation via chiral chromatography.4 We have developed a general and scalable approach based on asymmetric transfer hydrogenations (ATH) to control the planar chirality of pCps, enabling both the kinetic resolution of racemates5 and the desymmetrization of meso compounds.6 The resulting enantioenriched molecules, bearing diverse functional groups, served as key intermediates to rapidly access circularly polarized light emitters,7 organic photocatalysts,8 or antennas for lanthanide sensitization.9,10 Our strategy therefore offers a practical route to enantiopure pCps and opens new avenues for their application across various research domains.
References
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