Ruthenium-Catalyzed Alkylation of Cyclopropanols with Sulfoxonium Ylides via C–C Bond Cleavage: Formation of Diverse 1,5-Diketones

Abstract

A novel ruthenium-catalyzed alkylation of cyclopropanols with sulfoxonium ylides has been developed, which afford diverse 1,5-diketones with good efficiency and broad substrate scope. To illustrate the synthetic utilities of obtained 1,5-diketones, aldol and cyclization reactions have been investigated. The preliminary mechanistic studies suggest that this process involves a sequential C-C activation and carbene migratory insertion.

Ring‐Opening Cross‐Coupling/Cyclization Reaction of Cyclopropanols with Organic Compounds

“…Guan and Wu′s research group successfully employed a ruthenium complex for synthesizing diverse 1,5‐ diketone compounds 78 via C−C bond activation strategy (Scheme 42). [52] Ring‐opening of cyclopropanol 1 in the presence of Ru‐complex and sulfoxonium ylides 77 as carbene precursors afforded five‐membered ruthenacyclic intermediate A with extrusion of DMSO. Subsequent ring‐expansion and protodemetalation furnished desired product 78 .…”

Regio- and Enantioselective Asymmetric Transfer Hydrogenation of One Carbonyl Group in a Diketone through Steric Hindrance

“… Two 1,5-diketones, 33a and 33b , the precursors to alcohols 33b and 34b , were prepared through the reaction of cyclopropane 35 with 36 and 37 respectively, following a reported method (Supporting Information). Reduction of ketones 27a – 30a , 33a , and 34a using 1 mol % catalyst ( S,S )- 2 again gave ATH products 27b – 30b , 33b , and 34b in high ee (Figure ) in all cases other than the thiophene derivative 29b . The oxidation of 27b (97% ee) following the protocol in Figure resulted in formation of lactone 38 in >99% ee, although with only a 13% yield, presumably the result of intramolecular trapping of the intermediate ester by the hydroxy group following the oxidation with CAN.…”