Sugar‐Based Polymers from d‐Xylose: Living Cascade Polymerization, Tunable Degradation, and Small Molecule Release

Abstract

Enyne monomers derived from D‐xylose underwent living cascade polymerizations to prepare new polymers with a ring‐opened sugar and degradable linkage incorporated into every repeat unit of the backbone. Polymerizations were well‐controlled and had living character, which enabled the preparation of high molecular weight polymers with narrow molecular weight dispersity values and a block copolymer. By tuning the type of acid‐sensitive linkage (hemi‐aminal ether, acetal, or ether functional groups), we could change the degradation profile of the polymer and the identity of the resulting degradation products. For instance, the large difference in degradation rates between hemi‐aminal ether and ether‐based polymers enabled the sequential degradation of a block copolymer. Furthermore, we exploited the generation of furan‐based degradation products, from an acetal‐based polymer, to achieve the release of covalently bound reporter molecules upon degradation.

Bimolecular Coupling in Olefin Metathesis: Correlating Structure and Decomposition for Leading and Emerging Ruthenium−Carbene Catalysts

“…Olefin metathesis offers exceptional versatility in the catalytic assembly of carbon−carbon bonds. 1,2 Recent advances hold great promise for overcoming productivity challenges in frontier applications, including pharmaceutical manufacturing, 3 materials science, 4,5 and chemical biology. 6 Notwithstanding the groundbreaking impact of the dominant Ru−H 2 IMes catalysts, their facile decomposition is a fundamental limitation.…”

Toward E-selective Olefin Metathesis: Computational Design and Experimental Realization of Ruthenium Thio-Indolate Catalysts

“…Olefin metathesis offers an atomefficient catalytic alternative, in which olefinic fragments are rearranged by scission and regeneration of carbon-carbon double bonds [8][9][10]. Thanks to the ease of handling and functional-group tolerance of ruthenium catalysts [11][12][13], olefin metathesis has been widely adopted for the synthesis of complex organic molecules [14][15][16][17], including pharmaceuticals [18][19][20][21], and soft materials [22][23][24][25][26][27][28][29][30][31].…”

Trends in Polymer Degradation Across All Scales

“…Based on D ‐xylose derived monomers, the polymerization efficiency was further enhanced and enabled the incorporation of N‐, C‐, and O‐based linkers into the final polymeric architecture. [ 95 ] The resulting hemiaminal ether linkages within the backbone have different stabilities under acid conditions (Figure 8b), where the galactose derivative degrades faster than the glucose derivative in mild acidic conditions. Within block copolymers containing both functional groups, sequential degradation of the two different blocks was enabled, highlighting the potential of tunable degradation kinetics as a function of polymer architecture.…”