The Brantley Group published their work “General Access to Allene-Containing Polymers Using the Skattebøl Rearrangement” in ACS Macro Letters. Primary author is Nick Galan, graduate student in the Brantley Group.
Postsynthetic modification is a powerful strategy for tuning soft materials. While methods for side-chain functionalization abound, modifications of backbone structural elements can be difficult to achieve. This challenge arises, in part, from a lack of intrinsically reactive motifs that can be installed in the main chain of a polymer. Incorporating established synthetic handles into polymer architectures is paramount for overcoming this limitation.
Allenes are salient examples of moieties that could be leveraged in a wide range of postsynthetic modifications; however, the synthesis of a polyallene has proven elusive. Using the metathesis polymer of norbornene as a model architecture, the Brantley Group have established the Skattebøl rearrangement as a facile route to polyallenes. Polymers with varying allene content (20–95%) were readily prepared in excellent yields (89–94%). These materials possess unique optical properties and can be engaged through further postsynthetic modifications. As such, polyallenes could serve as valuable platforms for developing functional soft materials.
“Our results suggest that installing allenes within soft materials could open underexplored chemical space for polymer design and modification,” Galan said. “As such, we expect that our work will serve as a general platform for developing new types of tunable or stimulus-responsive materials.”