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1. Functionalized chalcogenide hybrid inorganic/organic polymers (CHIPs) via inverse vulcanization of elemental sulfur and vinylanilines

   https://doi.org/10.1039/c8py00270c  

   Zhang, Yueyan; Kleine, Tristan S.; Carothers, Kyle J.; Phan, David D.; Glass, Richard S.; Mackay, Michael E.; Char, Kookheon; Pyun, Jeffrey (January 2018, Polymer Chemistry)

   In this report, a new class of functional chalcogenide hybrid inorganic/organic polymers (CHIPs) bearing free aryl amine groups that are amenable to post-polymerization modifications were synthesized. These functional CHIPs were synthesized via the inverse vulcanization of elemental sulfur with 4-vinylaniline without the need for functional group protection of amines. This polymer is the first example of a polysulfide or CHIP material to carry a useful primary amine functional group which can be successfully post functionalized with acid chlorides and isocyanates to improve the mechanical properties. 

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2. Rational Design of an Organocatalyst for Peptide Bond Formation

   https://doi.org/10.1021/jacs.9b07742  

   Handoko, H.; Satishkumar, S.; Panigrahi, N. R.; Arora, P. S. (September 2019, Journal of the American Chemical Society)

   Amide bonds are ubiquitous in peptides, proteins, pharmaceuticals, and polymers. The formation of amide bonds is a straightforward process: amide bonds can be synthesized with relative ease because of the availability of efficient coupling agents. However, there is a substantive need for methods that do not require excess reagents. A catalyst that condenses amino acids could have an important impact by reducing the significant waste generated during peptide synthesis. We describe the rational design of a biomimetic catalyst that can efficiently couple amino acids featuring standard protecting groups. The catalyst design combines lessons learned from enzymes, peptide biosynthesis, and organocatalysts. Under optimized conditions, 5 mol % catalyst efficiently couples Fmoc amino acids without notable racemization. Importantly, we demonstrate that the catalyst is functional for the synthesis of oligopeptides on solid phase. This result is significant because it illustrates the potential of the catalyst to function on a substrate with a multitude of amide bonds, which may be expected to inhibit a hydrogen-bonding catalyst. 

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3. Expanding tricoordinate Au(I) complexes for efficient carbofunctionalization of alkynes to benzo-fused N-heterocycles and imines

   https://doi.org/10.1016/j.jcat.2025.116317  

   Akrofi-Mantey, Harold; Greif, Charles E; Odagwe, Ugochukwu B; Awuah, Samuel G (October 2025, Journal of Catalysis)

   Gold-catalyzed activation of alkynes towards functional molecules remains an interesting endeavor with industrial potential, yet stable, efficient catalysts are needed. Here, we report a shelf-stable tricoordinate Au(I) catalyst for the cyclization of anilino-alkyne derivatives to form C2-substituted indoles and other benzo-fused Nheterocycles. We also report the use of this Au(I) catalyst for intermolecular hydroamination of ethynylbenzene and diphenylacetylene with various aniline derivatives, forming imines. The distorted geometry of Au(I) complexes facilitates alkyne activation and demonstrates functional group tolerance of the catalyst under mild conditions. We expand the scope of previously synthesized benzo-fused N-heterocycles and demonstrate potential for tricoordinate complexes in catalytic systems. 

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4. Biobased Copolymers via Cationic Ring-Opening Copolymerization of Levoglucosan Derivatives and ε-Caprolactone

   https://doi.org/10.1021/acsmacrolett.3c00251  

   Porwal, Mayuri K.; Ellison, Christopher J.; Reineke, Theresa M. (July 2023, ACS Macro Letters)

   Simultaneous ring-opening copolymerization is a powerful strategy for the synthesis of highly functional copolymers from different types of cyclic monomers. Although copolymers are essential to the plastics industry, environmental concerns associated with current fossil-fuel-based synthetic polymers have led to an increasing interest in the use of renewable feedstock for polymer synthesis. Herein, we report a scalable synthetic platform to afford unique polysaccharides with different pendant functional groups from biomass-derived levoglucosan and ε-caprolactone via cationic ring-opening copolymerization (cROCOP). Biocompatible and recyclable bismuth triflate was identified as the optimal catalyst for cROCOP of levoglucosan. Copolymers from tribenzyl levoglucosan and ε-caprolactone, as well as from tribenzyl and triallyl levoglucosan, were successfully synthesized. The tribenzyl levoglucosan monomer composition ranged from 16% to 64% in the copolymers with ε-caprolactone and 22% to 79% in the copolymers with triallyl levoglucosan. The allylic levoglucosan copolymer can be utilized as a renewably derived scaffold to modify copolymer properties and create other polymer architectures via postpolymerization modification. Monomer reactivity ratios were determined to investigate the copolymer microstructure, indicating that levoglucosan-based copolymers have a gradient architecture. Additionally, we demonstrated that the copolymer glass transition temperature (Tg, ranging from −44.3 to 33.8 °C), thermal stability, and crystallization behavior could be tuned based on the copolymer composition. Overall, this work underscores the utility of levoglucosan as a bioderived feedstock for the development of functional sugar-based copolymers with applications ranging from sustainable materials to biomaterials. 

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5. Solution‐Doped Donor–Acceptor Copolymers Based on Diketopyrrolopyrrole and 3, 3′‐Bis (2‐(2‐(2‐Methoxyethoxy) Ethoxy) ethoxy)‐2, 2′‐Bithiophene Exhibiting Outstanding Thermoelectric Power Factors with p ‐Dopants

   https://doi.org/10.1002/adfm.202309646  

   Mukhopadhyaya, Tushita; Wagner, Justine; Lee, Taein D; Ganley, Connor; Tanwar, Swati; Raj, Piyush; Li, Lulin; Song, Yunjia; Melvin, Sophia J; Ji, Yuyang; et al (February 2024, Advanced Functional Materials)

   Katz, Howard (Ed.)

   Abstract The design of polymeric semiconductors exhibiting high electrical conductivity (σ) and thermoelectric power factor (PF) will be vital for flexible large‐area electronics. In this work, four polymers based on diketopyrrolopyrrole (DPP), 2,3‐dihydrothieno[3,4‐b][1,4]dioxine (EDOT), thieno[3,2‐b]thiophene (TT), and 3, 3′‐bis (2‐(2‐(2‐methoxyethoxy) ethoxy) ethoxy)‐2, 2′‐bithiophene (MEET) are investigated as side‐chains, with the MEET polymers newly synthesized for this study. These polymers are systematically doped with tetrafluorotetracyanoquinodimethane ( F₄TCNQ), CF3SO3H, and the synthesized dopant Cp(CN)₃‐(COOMe)₃, differing in geometry and electron affinity. The DPP‐EDOT‐based polymer containing MEET as side‐chains exhibits the highest conductivity (σ) ≈700 S cm−1 in this series with the acidic dopant (CF₃SO₃H). This polymer also shows the lowest oxidation potential by cyclic voltammetry (CV), the strongest intermolecular interactions evidenced by differential scanning calorimetry (DSC), and has the most oxygen‐based functionality for possible hydrogen bonding and ionic screening. Other polymers exhibit high σ ≈300–500 S cm−1 and power factor up to 300 µW m⁻¹K⁻². The mechanism of conductivity is predominantly electronic, as validated by time‐dependent conductance studies and transient thermo voltage monitoring over time, including for those doped with the acid. These materials maintain significant thermal stability and air stability over ≈6 weeks. Density functional theory calculations reveal molecular geometries and inform about frontier energy levels. Raman spectroscopy, in conjunction with scanning electron microscopy (SEM‐EDS) and x‐ray diffraction, provides insight into the solid‐state microstructure and degree of phase separation of the doped polymer films. Infrared spectroscopy enables this study to further quantify the degree of charge transfer from polymer to dopant. 

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