Divergent Rearrangement of Geminal-Substituted Cyclopropane: Access to Pyran and Spirocyclopropane Scaffolds

Herein, a chemodivergent protocol for accessing two distinct chemical spaces from a single starting material is reported. By varying the reaction conditions, O-center enolate and C-center enolate of modified geminal substituted cyclopropane 1,3 keto-esters furnished pyrans and spiro cyclopropanes, respectively. The developed protocol showed a broad functional group tolerance. Mechanistic and theoretical studies indicate that the reaction is initiated by keto group enolization and follows the HSAB principle, leading to distinct products in different media.