Enantioselective Access to the Parent Helicenols by Kinetic Resolution through Cu–H-Catalyzed Si–O Coupling

Abstract A Cu–H-catalyzed kinetic resolution of the parent [n]helicenols (n = 5, 6) through enantioselective dehydrogenative silylation with a secondary silane is reported. The dihydrosilane eventually employed is prochiral, thereby simultaneously establishing stereogenicity at the silicon atom as part of the resolution. The method provides highly enantioenriched helicenols and reveals a pronounced structure-selectivity relationship. Among the obtained products is a previously unknown, enantioenriched triflate-functionalized helicenol that enables further diversification through cross-coupling reactions.