Ligand-Controlled Cobalt-Catalyzed Regioselective Annulation: Divergent Synthesis of Indenols from o-Haloaromatic Ketones and Terminal Alkynes.

The annulation of o-haloaromatic ketones with terminal alkynes to access indenols remains a persistent challenge, with limited successful precedents reported to date. Herein, we disclose a cobalt-catalyzed ligand-controlled strategy for the divergent synthesis of indenols. By simple modulation of the ligand, the annulation of o-iodoaromatic ketones with terminal alkynes can be selectively achieved toward either 2- or 3-substituted indenols. This approach features excellent regioselectivity, a broad substrate scope, and late-stage modification.