Block copolymers containing both conducting and insulating segments are of interest due to their enhanced electrical properties arising from their increased crystallization. Yet few methods exist for generating these copolymers, because the reaction conditions for synthesizing each block are often incompatible. Herein, efforts toward identifying a one-pot, living polymerization method for synthesizing block copolymers of 1-pentene and 3-hexylthiophene is described. An in situ ligand exchange enables the optimal catalyst to be utilized for synthesizing each block. Even under these conditions, however, only homopolymers are observed. Computational studies modeling the ligand exchange reveal that the added stabilizing ligands likely inhibit propagation of the second block. These results suggest an ancillary ligand-based "goldilocks" effect wherein catalysts that are stable yet still reactive are required. (c) 2019 Wiley Periodicals, Inc.