Chemistry

Home » Brantley

Brantley

Brantley Group Published in JACS

by

The Brantley group recently published a paper in JACS entitled “Electroediting of Soft Polymer Backbones” Alan Fried, Breana Wilson, and Nick Galan contributed to the research, under the supervision of Johnathan Brantley.

The paper discusses new methodology for degradation and functionalization of olefin-containing polymers through electrochemistry. This method can be carried out in both homogeneous and heterogeneous systems, in addition to using mild conditions and being experimentally simple.

The work was completed in memory of Alan Fried.

Brantley Group Published in ACS Macro Letters

by

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.

Nicholas Galan
Nick Galan

“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.”

Brantley Group Published in Macromolecules

by

The Brantley Group published their work “Exploring Combinatorial Approaches to Polymer Diversification” in Macromolecules. 

Diversity-oriented strategies can facilitate the rapid exploration of chemical space during small-molecule synthesis, but similar approaches are underutilized for macromolecular substrates. Expanding the repertoire of soft material manipulations to accommodate iterative diversifications could enable the design of bespoke polymers with a range of novel structures and properties.

“To explore this concept, we chose to leverage the efficiency of Suzuki–Miyaura cross-coupling to rapidly access an array of functionalized polystyrene surrogates from a readily accessible polystyrene-p-pinacol boronic ester,” Brain Jacobs, postdoc, said. “A variety of C(sp2) electrophiles efficiently coupled with our model polymer (51–99% functionalization) in moderate-to-good yields (44–96%). “

Optimized coupling reactions afforded products with minimal changes in overall dispersity (as determined by gel permeation chromatography), which suggested that the desired coupling occurred with good fidelity. “Select products were subjected to further modifications (e.g., Wittig olefination, reduction, imine condensation) to showcase the diverse array of reactivities that can be accessed using our strategy.” Jacobs said.