Doubly Switchable Diastereodivergent Strategy Mediated by a Chiral Sulfoxide to Access Disubstituted Tetrahydrocyclopenta­pyranone and Hexahydrocyclopentapyranol Scaffolds via Nazarov Cyclization

Autor: Xavier J. Salom-Roig, Erwann Grenet, Arie van der Lee
Rok vydání: 2022
Předmět:
Zdroj: Synthesis. 55:580-597
ISSN: 1437-210X
0039-7881
Popis: Activated dienones bearing a chiral sulfoxide were transformed diastereodivergently into the corresponding disubstituted 3,4,5,6-tetrahydrocyclopenta[b]pyran-7(2H)-ones. The torquoselectivity of the reaction could be switched by changing the Lewis acid used as promoter. From the four possible stereoisomers, only the two trans were observed. In a second switchable diastereodivergent step, both corresponding diastereomeric 2,3,4,5,6,7-hexahydrocyclopenta[b]pyran-7-ols were obtained via the diastereoselective reduction of the ketone by changing the reducing agent. The Lewis acids as well as the reducing agents employed in both diastereodivergent steps were achiral, the diastereoselectivities being dictated by the sulfinyl auxiliary.
Databáze: OpenAIRE