Access to All-Carbon Spirocycles through a Carbene and Thiourea Cocatalytic Desymmetrization Cascade Reaction.
Shitian ZhuoTingshun ZhuLiejin ZhouChengli MouHuifang ChaiYunpeng LuLutai PanZhichao JinYonggui Robin ChiPublished in: Angewandte Chemie (International ed. in English) (2019)
A new catalytic approach for rapid asymmetric access to spirocycles is disclosed. The reaction involves a carbene- and thiourea-cocatalyzed desymmetrization process with the simultaneous installation of a spirocyclic core. The use of a thiourea cocatalyst is critical to turn on this reaction, as no product was formed in the absence of a thiourea. Our study constitutes the first success in the carbene-catalyzed enantioselective synthesis of all-carbon spirocycles. The reaction products can be readily transformed into sophisticated multicyclic molecules and chiral ligands.