Sulfone Units Research Articles

Chemiexcitation Acceleration of 1,2‐Dioxetanes by Spiro‐Fused Six‐Member Rings with Electron‐Withdrawing Motifs

AbstractThe chemiluminescent light‐emission pathway of phenoxy‐1,2‐dioxetane luminophores attracts growing interest within the scientific community. Dioxetane probes undergoing rapid flash‐type chemiexcitation exhibit higher detection sensitivity than those with a slow glow‐type chemiexcitation rate. We discovered that dioxetanes fused to non‐strained six‐member rings, with hetero atoms or inductive electron‐withdrawing groups, present both accelerated chemiexcitation rates and elevated chemical stability compared to dioxetanes fused to four‐member strained rings. DFT computational simulations supported the chemiexcitation acceleration observed by spiro‐fused six‐member rings with inductive electron‐withdrawing groups of dioxetanes. Specifically, a spiro‐dioxetane with a six‐member sulfone ring exhibited a chemiexcitation rate 293‐fold faster than that of spiro‐adamantyl‐dioxetane. A turn‐ON dioxetane probe for the detection of the enzyme β‐galactosidase, containing the six‐member sulfone unit, exhibited a S/N value of 108 in LB cell growth medium. This probe demonstrated a substantial increase in detection sensitivity towards E. coli bacterial cells expressing β‐galactosidase, with an LOD value that is 44‐fold more sensitive than that obtained by the adamantyl counterpart. The accelerated chemiexcitation and the elevated chemical stability presented by dioxetane containing a spiro‐fused six‐member ring with a sulfone inductive electron‐withdrawing group, make it an ideal candidate for designing efficient turn‐on chemiluminescent probes with exceptionally high detection sensitivity.

Chemiexcitation Acceleration of 1,2-Dioxetanes by Spiro-Fused Six-Member Rings with Electron-Withdrawing Motifs.

The chemiluminescent light-emission pathway of phenoxy-1,2-dioxetane luminophores attracts growing interest within the scientific community. Dioxetane probes undergoing rapid flash-type chemiexcitation exhibit higher detection sensitivity than those with a slow glow-type chemiexcitation rate. We discovered that dioxetanes fused to non-strained six-member rings, with hetero atoms or inductive electron-withdrawing groups, present both accelerated chemiexcitation rates and elevated chemical stability compared to dioxetanes fused to four-member strained rings. DFT computational simulations supported the chemiexcitation acceleration observed by spiro-fused six-member rings with inductive electron-withdrawing groups of dioxetanes. Specifically, a spiro-dioxetane with a six-member sulfone ring exhibited a chemiexcitation rate 293-fold faster than that of spiro-adamantyl-dioxetane. A turn-ON dioxetane probe for the detection of the enzyme β-galactosidase, containing the six-member sulfone unit, exhibited a S/N value of 108 in LB cell growth medium. This probe demonstrated a substantial increase in detection sensitivity towards E. coli bacterial cells expressing β-galactosidase, with an LOD value that is 44-fold more sensitive than that obtained by the adamantyl counterpart. The accelerated chemiexcitation and the elevated chemical stability presented by dioxetane containing a spiro-fused six-member ring with a sulfone inductive electron-withdrawing group, make it an ideal candidate for designing efficient turn-on chemiluminescent probes with exceptionally high detection sensitivity.

Multi-Substituted Phosphonated and Sulfonated Polymer Materials: Characterization and Blends with Basic Polymers

The growing demand for energy, limited resources, and climate warming call for alternative sustainable energy production. A promising candidate is the proton-exchange membrane fuel cell (PEMFC) using a proton conducting polymer as an electrolyte membrane. The most common proton-exchange membranes are based on sulfonated polymers, such as Nafion®. Since their proton conduction is driven by hydronium ions (H3O+) and hence require water, the operating temperature is limited to 100°C. Unlike in sulfonated polymer materials, the proton conduction in materials with phosphonic acid groups occurs via a hopping process and does not require water.1 This study introduces a highly substituted phosphonated and sulfonated polymer based on poly(pentafluorostyrene), which makes the material adaptable in anhydrous and hydrous operating conditions since the phosphonic acid and sulfonic acid units can conduct cooperatively. The phosphonic acid group is introduced via the nucleophilic aromatic substitution Michaelis-Arbuzov reaction. The Para-Fluoro-Thiol reaction was used to introduce sulfonic acid groups into the polymer backbone. In the past, both reaction steps were well investigated.2,3 The highly substituted polymer material was blended with a basic polymer to circumvent water solubility and investigated according to its proton conductivity, thermal stability, and mechanical properties.(1) Kumar, A. J. Mater. Chem. A 2020, 8 (43), 22632–22636. DOI: 10.1039/d0ta07732a.(2) Atanasov, V.; Oleynikov, A.; Xia, J.; Lyonnard, S.; Kerres, J. Journal of Power Sources 2017, 343, 364–372. DOI: 10.1016/j.jpowsour.2017.01.085.(3) Delaittre, G.; Barner, L. Polym. Chem. 2018, 9 (20), 2679–2684. DOI: 10.1039/c8py00287h.

Mixed‐Linker Strategy for the Construction of Sulfone‐Containing D–A–A Covalent Organic Frameworks for Efficient Photocatalytic Hydrogen Peroxide Production

AbstractThe solar‐driven photocatalytic production of hydrogen peroxide (H2O2) from water and oxygen using semiconductor catalysts offers a promising approach for converting solar energy into storable chemical energy. However, the efficiency of photocatalytic H2O2 production is often restricted by the low photo‐generated charge separation, slow surface reactions and inadequate stability. Here, we developed a mixed‐linker strategy to build a donor‐acceptor‐acceptor (D–A–A) type covalent organic framework (COF) photocatalyst, FS‐OHOMe‐COF. The FS‐OHOMe‐COF structure features extended π–π conjugation that improves charge mobility, while the introduction of sulfone units not only as active sites facilitates surface reactions with water but also bolsters stability through increased interlayer forces. The resulting FS‐OHOMe‐COF has a low exciton binding energy, long excited‐state lifetime and high photo‐stability that leads to high performance for photocatalytic H2O2 production (up to 1.0 mM h−1) with an H2O2 output of 19 mM after 72 hours of irradiation. Furthermore, the catalyst demonstrates high stability, which sustained activity over 192 hours of photocatalytic experiment.

Mixed-Linker Strategy for the Construction of Sulfone-Containing D-A-A Covalent Organic Frameworks for Efficient Photocatalytic Hydrogen Peroxide Production.

The solar-driven photocatalytic production of hydrogen peroxide (H2O2) from water and oxygen using semiconductor catalysts offers a promising approach for converting solar energy into storable chemical energy. However, the efficiency of photocatalytic H2O2 production is often restricted by the low photo-generated charge separation, slow surface reactions and inadequate stability. Here, we developed a mixed-linker strategy to build a donor-acceptor-acceptor (D-A-A) type covalent organic framework (COF) photocatalyst, FS-OHOMe-COF. The FS-OHOMe-COF structure features extended π-π conjugation that improves charge mobility, while the introduction of sulfone units not only as active sites facilitates surface reactions with water but also bolsters stability through increased interlayer forces. The resulting FS-OHOMe-COF has a low exciton binding energy, long excited-state lifetime and high photo-stability that leads to high performance for photocatalytic H2O2 production (up to 1.0 mM h-1) with an H2O2 output of 19 mM after 72 hours of irradiation. Furthermore, the catalyst demonstrates high stability, which sustained activity over 192 hours of photocatalytic experiment.

Synthesis of Biobased Poly(butylene Furandicarboxylate) Containing Polysulfone with Excellent Thermal Resistance Properties.

A synthetic biopolymer derived from furandicarboxylic acid monomer and hydroxyethyl-terminated poly(ether sulfone) is presented. The synthesis involves 4,4'-dichlorodiphenyl sulfone and 4,4-dihydroxydiphenyl sulfone, resulting in poly(butylene furandicarboxylate)-poly(ether sulfone) copolyesters (PBFES) through melt polycondensation with titanium-catalyzed polymerization. This facile method yields segmented polyesters incorporating polysulfone, creating a versatile group of high-temperature thermoplastics with adjustable thermomechanical properties. The PBFES copolyesters demonstrate an impressive tensile modulus of 2830 MPa and a tensile strength of 84 MPa for PBFES55. Additionally, the poly(ether sulfone) unit imparts a relatively high glass transition temperature (Tg), ranging from 36.6 °C for poly(butylene 2,5-furandicarboxylate) to 112.3 °C for PBFES62. Moreover, the complete amorphous film of PBFES exhibits excellent transparency and solvent resistance, making it suitable for applications, such as food packaging materials.

Palladium-catalyzed four-component domino sulfonylation and carbonylation of 1,3-enynes at room temperature

A novel palladium-catalyzed four-component domino sulfonylation and carbonylation of 1,3-enynes has been developed, which enables the rapid incorporation of allene, sulfone, carbonyl and amine units into one single molecule simultaneously.

Metal-free synthesis of γ-ketosulfones through Brønsted acid-promoted conjugate addition of sulfinamides.

A straightforward and general metal-free method has been developed to add sufinamide-derived sulfone units on Michael acceptors under mild conditions. This reaction enables the preparation of a large variety of original γ-ketosulfones, of which only a few synthetic methods have been reported. The mild reaction conditions used tolerate a wide diversity of functional groups and empower the implementation of a late-stage functionalisation strategy.

Sulfone-bridged difuran polyesters

Oxidation of 5,5′-sulfanediyldi(furan-2-carboxylic acid) in acetic acid with aqueous hydrogen peroxide was used to prepare a new dicarboxylic monomer with a central sulfone group flanked by two biomass-derived furan rings. The new sulfone monomer was reacted with ethylene glycol, 1,3-propanediol, 1,4-butanediol, and 1,5-pentanediol to prepare new homopolyesters. Of these diols, 1,5-pentanediol yielded polyester with the most favorable properties in terms of processability and appearance. It could also be recycled back into the starting monomer under mild conditions. Using 1,5-pentanediol, a copolyester containing a 1:1 mixture of sulfone and sulfide difuran units was also prepared for testing alongside the corresponding sulfone difuran homopolyester. From measurements carried out on film samples of these two new materials, it was found that the new sulfone monomer will lead to polyester materials with high glass transition temperatures, high tensile stiffnesses, and low O2 permeability. The nature of the side reactions related to the difuran sulfone moiety under high temperatures remained unclear, as thermogravimetric analysis indicated relatively good stability characteristics and the monomer appeared relatively stable even at high temperatures.

Amphiphilic properties of 2-(acrylamido)dodecanesulfonic acid and its water-soluble copolymers with alkoxyoligo(ethylene glycol)methacrylates

The surface-active properties (in aqueous solutions and water-hexane mixtures) of the amphiphilic sulfo-containing macromonomer 2-(acrylamido)dodecanesulfonic acid (AAС12SА) were studied; copolymers of this surfomer with oligo(ethylene glycol)methacrylates were synthesized. Тhe effect of the content of sulfonic units in the obtained molecular brushes on their thermosensitive properties in water and water-salt solutions was determined.

Integration of aggregation-induced emission and intramolecular charge transfer in a V-shaped organic donor-acceptor

Coumarin, an oxadiazole, and the V-shaped structural characteristic of a sulfone have been integrated to create a new symmetric compound, and the compound was characterized. The synthesized molecule was used as an emitter and an electron transporter in three different device configurations. The sulfone units induced a V-shaped structure that weakened the π-π stacking and thus limited aggregation-induced quenching. The molecule emitted strong fluorescence in the amorphous solid state, in a membrane, and in a non-polar solvent. From thermogravimetry and differential scanning calorimetry, the compound shows good thermal stability (381 °C) and glass-transition temperature (125 °C). The solvatochromism phenomenon and electrochemical properties were investigated in detail by fluorescence spectroscopy and cyclic voltammetry. Time-dependent density functional theory calculations were performed to understand the photophysical properties. This new type of compound exhibits tunable light emission in solution, making it a versatile emitter.

Effect of amphiphilic copolymers of oligo(ethylene glycol)methacrylates on the synthesis of N-(dibutylaminomethyl)methacrylamide in an aqueous-organic emulsion

The accelerating effect of adding a low molecular weight sulfonic acid surfactant (alkylbenzenesulfonic acid) and nonionic or containing sulfonic acid units amphiphilic copolymers of methoxy- and higher alkoxyoligo(ethylene glycol)methacrylates on the synthesis of a promising cationic monomer, N-(dibutylaminomethyl)methacrylamide, proceeding in an aqueous-amine emulsion, by the Mannich reaction, was revealed. The infl uence of the concentration of additives and the structure of copolymers on the catalytic effect is shown.

Highly Efficient Doping‐Free Thermally Activated Delayed Fluorescent Organic Light‐Emitting Diodes with an Ultrathin Quasi‐Host‐Guest Emission Layer

AbstractDoping‐free organic light‐emitting diodes (OLEDs) are beneficial to reduce manufacturing costs for mass production, which, however, are limited by the ubiquitous aggregation‐caused quenching (ACQ) effect, especially for thermally activated delayed fluorescence (TADF) emitters with relatively long exciton lifetimes. Herein, two typical TADF emitters pACRS and pACRSO with different sulfur atom valence states are developed, where pACRS with a thioether unit exhibits suppressed intermolecular interaction, alleviated ACQ effect, and higher efficiency in a conventional doping‐free device, in contract to pACRSO with a sulfone unit. It is of interest that comparable efficiencies are achieved for both emitters in doping‐free OLEDs with an ultrathin emission layer (UEML), in which the emitter molecules are deposited onto the surface of the underlying organic layer of host material to form an ultrathin quasi‐host‐guest system with alleviated ACQ effect. Besides, the suppressed trap effect is the key to guarantee the efficiency of UEML‐OLEDs, while different intermolecular interactions of emitters that determine the optimized UEML thickness will affect the efficiency roll‐off. Furthermore, benefiting from the UEML structure, highly efficient doping‐free OLEDs are also successfully achieved for red TADF emitters with stronger intermolecular interactions. Such an UEML strategy meeting efficiency and cost demands holds great promise for doping‐free OLEDs.

Sulfone‐Modified Covalent Organic Frameworks Enabling Efficient Photocatalytic Hydrogen Peroxide Generation via One‐Step Two‐Electron O2 Reduction

AbstractPhotocatalytic oxygen reduction reaction (ORR) offers a promising hydrogen peroxide (H2O2) synthetic strategy, especially the one‐step two‐electron (2e−) ORR route holds great potential in achieving highly efficient and selectivity. However, efficient one‐step 2e− ORR is rarely harvested and the underlying mechanism for regulating the ORR pathways remains greatly obscure. Here, by loading sulfone units into covalent organic frameworks (FS‐COFs), we present an efficient photocatalyst for H2O2 generation via one‐step 2e− ORR from pure water and air. Under visible light irradiation, FS‐COFs exert a superb H2O2 yield of 3904.2 μmol h−1 g−1, outperforming most reported metal‐free catalysts under similar conditions. Experimental and theoretical investigation reveals that the sulfone units accelerate the separation of photoinduced electron‐hole (e−‐h+) pairs, enhance the protonation of COFs, and promote O2 adsorption in the Yeager‐type, which jointly alters the reaction process from two‐step 2e− ORR to the one‐step one, thereby achieving efficient H2O2 generation with high selectivity.

Sulfone-Modified Covalent Organic Frameworks Enabling Efficient Photocatalytic Hydrogen Peroxide Generation via One-Step Two-Electron O2 Reduction.

Photocatalytic oxygen reduction reaction (ORR) offers a promising hydrogen peroxide (H2 O2 ) synthetic strategy, especially the one-step two-electron (2e- ) ORR route holds great potential in achieving highly efficient and selectivity. However, efficient one-step 2e- ORR is rarely harvested and the underlying mechanism for regulating the ORR pathways remains greatly obscure. Here, by loading sulfone units into covalent organic frameworks (FS-COFs), we present an efficient photocatalyst for H2 O2 generation via one-step 2e- ORR from pure water and air. Under visible light irradiation, FS-COFs exert a superb H2 O2 yield of 3904.2 μmol h-1 g-1 , outperforming most reported metal-free catalysts under similar conditions. Experimental and theoretical investigation reveals that the sulfone units accelerate the separation of photoinduced electron-hole (e- -h+ ) pairs, enhance the protonation of COFs, and promote O2 adsorption in the Yeager-type, which jointly alters the reaction process from two-step 2e- ORR to the one-step one, thereby achieving efficient H2 O2 generation with high selectivity.

Sulfonic-Pendent Vinylene-Linked Covalent Organic Frameworks Enabling Benchmark Potential in Advanced Energy.

Both proton exchange membrane fuel cells and uranium-based nuclear techniques represent two green and advanced energies. However, both of them still face some intractable scientific and industrial problems. For the former, established proton-conduction materials always suffer one or another defect such as low proton conductivity, high activation energy, bad durability, or just small-scale product; while for the later, there still lacks available adsorbent to selectively recover of UO2 2+ from concentrated nitric acid (>1M) during the spent fuel reprocessing due to the deactivation of the adsorption site or the decomposition of adsorbent under such rigorous conditions. It is found that the above two issues can be well solved by the construction of sulfonic-pendent vinylene-linked covalent organic frameworks (COFs), since these COFs contain abundant sulfonic units for both intrinsic proton conduction and UO2 2+ capture through strong coordination fixation and vinylene linkage that enhances the stability up to 12M nitric acid (one of the best materials surviving in 12M HNO3 ).

Effects of the protonation and the polar solvation on the molecular properties of methyl orange: A density functional theory study

AbstractMethyl orange (MO) and its protonated derivatives were investigated at the density functional theory (DFT) level using CAM‐B3LYP functional and 6‐311 + G(d,p) basis sets; their absorption spectra in aqueous solution were simulated, their relative stabilities in both the gas phase and the polar solutions were calculated, and the activation energy barrier for the cis‐to‐trans isomerization in both phases were computed. Except the protonation at the amino group, all the protonated isomers show a bathochromic shift of the most intense absorption peak. In the gas phase, the sulfonate unit turns out to be the most favorable proton acceptor. In the polar solutions, however, azo groups are more effective to accept the proton. The protonation at the azo N atom next to the phenyl‐sulfonate group significantly reduces the energy barrier for the cis‐to‐trans conversion in the aqueous solution, which suggests a swift conversion in the ground state.

An artificial light-harvesting system constructed from a water-soluble metal-organic barrel for photocatalytic aerobic reactions in aqueous media.

An artificial light-harvesting system constructed from a water-soluble host-guest complex can be regarded as a high-level conceptual model of its biological counterpart and can convert solar energy into chemical energy in an aqueous environment. Herein, a water-soluble metal-organic barrel Ga-tpe with twelve sulfonic acid units was obtained by subcomponent self-assembly between Ga3+ ions and tetra-topic ligands with tetraphenylethylene (TPE) cores. By taking advantage of host-guest interactions, cationic dye rhodamine B (RB) was constrained in the pocket of Ga-tpe to promote the Förster resonance energy transfer (FRET) process for efficient photocatalytic aerobic oxidation of sulfides and cross-dehydrogenative coupling (CDC) reaction in aqueous media.

Structure-Performance relationship guided design and strategic synthesis of lithiated oxa-graphene for high lithium storage

Graphene derivative materials are widely used as anode component in lithium-ion batteries. However, there is still a lack of reliable and foresighted guides helpful for designing high-performance graphene-based electrode materials. To this end, we strategically chose challenging graphite fluoride as starting material for the derivatization of graphene in order to exclude interference factors. As a result, graphene framework was functionalized with oxygen-containing carboxylate and sulfonate groups and oxygen-free aniline units at a similar functionalization degree. Due to the strong effect of lithiation, out-of-plane p-aminobenzoic acid blocks boosted the lithium-storage capacity of graphene matrix to 636 mAh g−1 at 0.1 A/g, and sulfanilic acid blocks maximized this value to 873 mAh g−1. Sadly, oxygen-free aniline functionalized graphene material only delivered a specific capacity of 88 mAh g−1. Meanwhile, spatial lithiated carboxylate and sulfonate units endowed graphene framework with better rate capability and cycling stability. Such a structure-performance relationship established herein was beneficial for the design and preparation of high-performance graphene derivative electrode materials.

Electrospun Poly(acrylic acid-co-4-styrene sulfonate) as Potential Drug-Eluting Scaffolds for Targeted Chemotherapeutic Delivery Systems on Gastric (AGS) and Breast (MDA-Mb-231) Cancer Cell Lines.

Potential drug-eluting scaffolds of electrospun poly(acrylic acid-co-styrene sulfonate) P(AA-co-SS) in clonogenic assays using tumorigenic gastric and ovarian cancer cells were tested in vitro. Electrospun polymer nanofiber (EPnF) meshes of PAA and PSSNa homo- and P(AA-co-SS) copolymer composed of 30:70, 50:50, 70:30 acrylic acid (AA) and sodium 4-styrene sulfonate (SSNa) units were performed by electrospinning (ES). The synthesis, structural and morphological characterization of all EPnF meshes were analyzed by optical and electron microscopy (SEM-EDS), infrared spectroscopy (FTIR), contact angle, and X-ray diffraction (XRD) measurements. This study shows that different ratio of AA and SSNa of monomers in P(AA-co-SS) EPnF play a crucial role in clonogenic in vitro assays. We found that 50:50 P(AA-co-SS) EPnF mesh loaded with antineoplastic drugs can be an excellent suppressor of growth-independent anchored capacities in vitro assays and a good subcutaneous drug delivery system for chemotherapeutic medication in vivo model for surgical resection procedures in cancer research.