Collective Synthesis of Chiral Tetrasubstituted Cyclobutanes Enabled by Enantioconvergent Negishi Cross‐Coupling of Cyclobutenones.

Cyclobutenones provide a straightforward four‐carbon ring platform for further structural elaborations in that every carbon atom of the ring could be potentially functionalized. We report here a nickel catalyzed enantioconvergent Negishi coupling of 4‐iodocyclobutenones with an array of aryl or alkenyl zinc reagents to access enantioenriched 4‐substituted cyclobutenones, from which a modular approach to the synthesis of 1,2,3,4‐tetrasubstituted cyclobutanes was demonstrated. [ABSTRACT FROM AUTHOR]