Nickel‐Catalyzed Ring Expansion of Cyclobutanones towards Indanones

Despite recent advances in catalytic ring‐opening/cross‐coupling process of o‐halogen tethered phenylcyclobutanones with other partners, single‐component ring expansion of such precursors towards 3‐methylindanones has not been disclosed. We present herein a nickel catalyzed C−C bond reconstruction sequence of o‐bromophenylcyclobutanones using H2O as hydrogen donor, leading to a series of indanones, which can be further converted into other benzene‐fused cyclic compounds.