Substrate-Controlled Divergent Synthesis of Multisubstituted Cyclopentenones and 1,4-Diketones

Multisubstituted cyclopentenones and 1,4-diketones are valuable chemicals for synthesizing biologically relevant compounds. We established the Rh(III)-catalyzed divergent synthesis of multisubstituted cyclopentenones and 1,4-diketones from quinoline-8-carbaldehydes and cyclopropanols. Switchable product selectivity was achieved using different cyclopropyl alcohols under the optimized reaction conditions. Multisubstituted cyclopentenones were obtained through aldehydic C-H activation, C-C bond cleavage of 1-benzyl-substituted cyclopropyl alcohols, and subsequent intramolecular cyclizations. Notably, 1-phenethyl-, 1-aryl-, and 1-alkyl-substituted cyclopropyl alcohols function as alkylating agents, affording 1,4-diketones via aldehydic C-H activation.