Diastereoselective Ring Expansion of Cyclic Ketones Enabled by HAT-Initiated Radical Cascade

Herein we disclose an iron-catalyzed method for stereoselective synthesis of multisubstituted cyclic ketones containing a synthetically challenging quaternary carbon from readily accessible beta-vinyl keto esters in good yields. This cascade reaction is initiated by a hydrogen atom transfer (HAT) process, after which a Dowd-Beckwith-type ring-expansion reaction occurs. This strategic transformation offers access to synthetically valuable cyclic ketones bearing two contiguous stereocenters, including quaternary stereocenters, which hold paramount significance within the realm of synthetic chemistry.

Automated summary

In this study, we disclose an iron-catalyzed method for the stereoselective synthesis of multisubstituted cyclic ketones containing synthetically challenging quaternary carbons. The cascade reaction involves a hydrogen atom transfer (HAT) process followed by a Dowd-Beckwith-type ring-expansion reaction. This strategic transformation provides access to valuable cyclic ketones bearing two contiguous stereocenters, including quaternary stereocenters, which are of paramount significance in synthetic chemistry.