Nickelacyclobutanes are mostly invoked as reactive intermediates in the reaction of nickel carbenes and olefins to yield cyclopropanes. Nevertheless, early work suggested that other decomposition routes such as β-hydride elimination and even metathesis could be accessible. Herein, we report the isolation and characterization of a stable pentacoordinated nickelacyclobutane incorporated in a pincer complex. The coordination of different coligands to the nickelacyclobutane determines its selective decomposition along cyclopropanation, metathesis or apparent β-hydride elimination pathways. DFT calculations shed light on the mechanism of these different pathways.
Keywords: cyclopropanation; metallacycles; metathesis; nickel; pincer compounds.
© 2021 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.