Precise cooperative sulfur placement leads to semi-crystallinity and selective depolymerisability in CS2/oxetane copolymers

Nature Communications, Год журнала: 2023, Номер 14(1)

Опубликована: Июль 27, 2023

CS2 promises easy access to degradable sulfur-rich polymers and insights into how main-group derivatisation affects polymer formation properties, though its ring-opening copolymerisation is plagued by low linkage selectivity small-molecule by-products. We demonstrate that a cooperative Cr(III)/K catalyst selectively delivers poly(dithiocarbonates) from oxetanes while state-of-the-art strategies produce scrambled heterocyclic The formal introduction of sulfur centres the parent polycarbonates results in net shift polymerisation equilibrium towards, therefore facilitating, depolymerisation. During however, enables near quantitative generation metastable high sequence limiting lifetime alkoxide intermediates. Furthermore, key obtain semi-crystalline materials can be moulded self-standing objects as well enable chemoselective depolymerisation cyclic dithiocarbonates which themselves serve monomers polymerisation. Our report demonstrates potential catalysis previously inaccessible rich with beneficial chemical physical properties.

Язык: Английский

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Co(II)–N4 Catalysts for the Coupling of CO₂ with Epoxides into Cyclic Carbonates: Catalytic Activity, Computational and Kinetic Studies

Inorganic Chemistry, Год журнала: 2024, Номер 63(20), С. 9156 - 9163

Опубликована: Май 7, 2024

In this study, we synthesized and characterized a series of cobalt(II) complexes bearing linear tetradentate N4 ligands. These Co(II)-N4 proved to be efficient catalysts for the cycloaddition reaction between carbon dioxide epoxides even at room temperature 1 bar pressure without need solvents or cocatalysts. Furthermore, when combined with (triphenylphosphoranylidene)ammonium chloride (PPNCl) as cocatalyst, Co-N4 exhibited an impressive turnover frequency up 41,000 h

Язык: Английский

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Quantifying CO₂ Insertion Equilibria for Low-Pressure Propene Oxide and Carbon Dioxide Ring Opening Copolymerization Catalysts

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(15), С. 10451 - 10464

Опубликована: Апрель 8, 2024

While outstanding catalysts are known for the ring-opening copolymerization (ROCOP) of CO2 and propene oxide (PO), few reported at low pressure. Here, a new series Co(III)M(I) heterodinuclear compared. The Co(III)K(I) complex shows best activity (TOF = 1728 h–1) selectivity (>90% polymer, >99% CO2) is highly effective pressures (<10 bar). insertion prerate determining chemical equilibrium step. At pressures, concentration active catalyst depends on pressure; above 12 bar, its saturated, rates independent pressure, allowing constant to be quantified first time (Keq 1.27 M–1). A unified rate law, applicable under all operating conditions, presented. As proof potential, published data leading literature reinterpreted constants estimated, showing that this law applies other systems.

Язык: Английский

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Evolution of Copolymers of Epoxides and CO₂: Catalysts, Monomers, Architectures, and Applications

Chemical Reviews, Год журнала: 2024, Номер unknown

Опубликована: Окт. 25, 2024

The copolymerization of CO

Язык: Английский

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Exterior decorating: Lewis acid secondary coordination spheres for cooperative reactivity

Trends in Chemistry, Год журнала: 2022, Номер 4(4), С. 331 - 346

Опубликована: Фев. 21, 2022

Язык: Английский

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