Remote Control Grubbs Catalysts That Modulate Ring-Opening Metathesis Polymerizations

A broad range of stimuli, including light, heat, mechanical force, or changes in chemical potential, may be used to toggle Ru-based catalysts between multiple distinct states of activity. Catalysts with such features offer a means to temporally- and, in some cases, spatially-control a variety of polymerizations, and thus should facilitate access to synthetic macromolecular materials with tunable structures and properties. Due to the intrinsic versatility and robustness of the Grubbs-type catalyst platforms, numerous remotely controlled ring-opening metathesis polymerizations have been introduced. Herein, selected examples of stimuli-responsive catalysts that have been recently used for such purposes are surveyed and discussed. Perspectives on potential opportunities for development and growth as well as an outlook for the field are also provided. (C) 2017 Wiley Periodicals, Inc.