Synthesis and Reactivity of Metallocarbene-Containing Polymers

Metallopolymers are an emerging class of materials with potential utility as semiconductors, catalysts, optical device components, and stimuli responsive networks. While polymer frameworks have been decorated with an array of organometallic moieties, the incorporation of metallocarbenes has been largely overlooked. Here, we report ring-opening metathesis polymerization as a strategy for the synthesis of Fischer carbene-containing polymers. High degrees of polymerization were observed (>800 repeats), and the isolated materials exhibited exceptional solubility and thermal stability. The tungsten carbene subunits were readily incorporated into block copolymers and could be modified through subsequent transformations. Moreover, the metallocarbene polymers were found to release carbon monoxide upon exposure to light or oxygen, which is unusual for tungsten carbene complexes. These metallocarbene-containing polymers could represent new platforms for the development of functional materials.