Cobalt-Catalyzed Double Carbonylation of Cyclopropenes through a Stereodivergent β-Alkenyl Ketene Pathway

Ketenes represent an important class of reactive intermediates that serve as key precursors in pharmaceutical and organic synthesis, enabling access to a diverse array of multifunctional and valuable compounds. Herein, we report a novel strategy for cobalt-catalyzed double carbonylation of cyclopropenes with carbon monoxide that proceeds via in situ-generated <i>E</i>- and <i>Z</i>-configured ketenes species, whose complementary roles are essential for the reaction's success. This transformation exhibits a broad substrate scope and delivers a series of naphthyl allylates with high <i>E</i>-selectivity. Furthermore, a detailed and coherent catalytic mechanism is proposed based on systematic experimental studies and DFT calculations. This work offers a new perspective for the advancement of ketene chemistry.