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Zhao JZ, Yue TJ, Ren BH, Liu Y, Ren WM, Lu XB. Recyclable Sulfur-Rich Polymers with Enhanced Thermal, Mechanical, and Optical Performance. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c01628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Ren BH, Teng YQ, Wang SN, Wang S, Liu Y, Ren WM, Lu XB. Mechanistic Basis for the High Enantioselectivity and Activity in the Multichiral Bimetallic Complex-Mediated Enantioselective Copolymerization of meso-Epoxides. ACS Catal 2022. [DOI: 10.1021/acscatal.2c03659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Yu Y, Gao B, Liu Y, Lu XB. Efficient and Selective Chemical Recycling of CO 2 -Based Alicyclic Polycarbonates via Catalytic Pyrolysis. Angew Chem Int Ed Engl 2022; 61:e202204492. [PMID: 35770495 DOI: 10.1002/anie.202204492] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Indexed: 01/22/2023]
Abstract
Chemical recycling of polymers to their constituent monomers is the foremost challenge in building a sustainable circular plastics economy. Here, we report a strategy for highly efficient depolymerization of various CO2 -based alicyclic polycarbonates to epoxide monomers in solvent-free conditions by a simple CrIII -Salen complex mediated catalytic pyrolysis process. The chemical recycling of the widely studied poly(cyclohexene carbonate) exhibits excellent reactivity (TOF up to 3000 h-1 , 0.1 mol % catalyst loading) and high epoxide monomer selectivity (>99 %). Mechanistic investigation reveals that the process proceeds in a sequential fashion via a trans-carbonate intermediate.
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Tang D, Maihebuba B, Sun XF, Lu XB. [Analysis of pathogenic bacteria in cirrhotic patients complicated with bacterial infection in a tertiary hospital in Xinjiang]. ZHONGHUA GAN ZANG BING ZA ZHI = ZHONGHUA GANZANGBING ZAZHI = CHINESE JOURNAL OF HEPATOLOGY 2022; 30:885-888. [PMID: 36207946 DOI: 10.3760/cma.j.cn501113-20201224-00677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Objective: To understand the species, distribution, and extent of drug resistance of pathogenic bacteria in patients with liver cirrhosis combined with bacterial infection in a tertiary hospital in Xinjiang. Methods: 1 271 cases with liver cirrhosis combined with infection were analyzed retrospectively for pathogenic bacterial species and drug resistance condition in different bacterial strain. Results: Among the 1 271 cases with liver cirrhosis, 480 were combined with infection, and the infection rate was 37.8%. The majority of infected patients had decompensated cirrhosis (438 cases). Peritoneum (327 cases, 60.8%) was the common infection site, followed by lungs (16.9%). 343 strains of pathogens were isolated from 480 infected cases, of which 289 strains were among the top 10 common distinct bacteria, accounting for 76.5% and 23.5% of Gram-negative and positive bacteria. The first top three strains were Escherichia coli. (33.2%), Klebsiella pneumoniae (11.4%), and Enterococcus faecium (11.1%), and there were differences in the drug resistance rates of each strain. Conclusion: In a tertiary hospital in Xinjiang, patients with decompensated cirrhosis have a high rate of bacterial infection. The pathogenic bacteria are diverse, mainly Gram-negative bacteria; however, the infection rate of Gram-positive bacteria such as Enterococcus is gradually increasing. Additionally, according to the bacterial properties, they are divided into four categories: Enterobacter, Enterococcus, glucose non-fermenting bacteria and Staphylococcus, and it is found that even the same species of bacteria have different drug resistance rates.
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Zhang K, Ren BH, Liu XF, Wang LL, Zhang M, Ren WM, Lu XB, Zhang WZ. Direct and Selective Electrocarboxylation of Styrene Oxides with CO2 for Accessing β‐Hydroxy Acids. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202207660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Zhang K, Ren BH, Liu XF, Wang LL, Zhang M, Ren WM, Lu XB, Zhang WZ. Direct and Selective Electrocarboxylation of Styrene Oxides with CO2 for Accessing β-Hydroxy Acids. Angew Chem Int Ed Engl 2022; 61:e202207660. [PMID: 35862121 DOI: 10.1002/anie.202207660] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Indexed: 11/08/2022]
Abstract
Highly selective and direct electroreductive ring-opening carboxylation of epoxides with CO2 in an undivided cell is reported. This reaction shows broad substrate scopes within styrene oxides under mild conditions, providing practical and scalable access to important synthetic intermediate β-hydroxy acids. Mechanistic studies show that CO2 functions not only as a carboxylative reagent in this reaction but also as a promoter to enable efficient and chemoselective transformation of epoxides under additive-free electrochemical conditions. Cathodically generated α-radical and α-carbanion intermediates lead to the regioselective formation of α-carboxylation products.
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Chen SY, Ren BH, Li SH, Song YH, Jiao S, Zou C, Chen C, Lu XB, Liu Y. Cationic P,O-Coordinated Nickel(II) Catalysts for Carbonylative Polymerization of Ethylene: Unexpected Productivity via Subtle Electronic Variation. Angew Chem Int Ed Engl 2022; 61:e202204126. [PMID: 35575978 DOI: 10.1002/anie.202204126] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Indexed: 11/06/2022]
Abstract
Transition-metal-catalyzed copolymerization of ethylene with carbon monoxide affords polyketones materials with excellent mechanical strength, photodegradability, surface and barrier properties. Unlike the widely used and rather expensive Pd catalysts, Ni-catalyzed carbonylative polymerization is very difficult since the strong binding affinity of CO to Ni deactivates the highly electrophilic metal center easily. In this study, various cationic P,O-coordinated Ni complexes were synthesized using the electronic modulation strategy, and the catalyst with strong electron-donating substituents exhibits an excellent productivity of 104 g polymer (g Ni)-1 , which represents a rare discovery that a Ni complex could operate with such exceptional efficiency in comparison with Pd catalysts. Notably, those Ni catalysts were also efficient for terpolymerization of ethylene, propylene with CO for producing commercial polyketone materials with low melting temperatures and easy processibility.
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Yu Y, Gao B, Liu Y, Lu XB. Efficient and Selective Chemical Recycling of CO2‐based Alicyclic Polycarbonates via Catalytic Pyrolysis. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202204492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Lu XB, Ren BH. Partners in Epoxide Copolymerization Catalysis: Approach to High Activity and Selectivity. CHINESE JOURNAL OF POLYMER SCIENCE 2022. [DOI: 10.1007/s10118-022-2744-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Liu AH, Ma GT, Ren BH, Zhang JY, Lu XB. Alkoxy-Functionalized Amines as Single-Component Water-Lean CO 2 Absorbents with High Efficiency: The Benefit of Stabilized Carbamic Acid. Ind Eng Chem Res 2022. [DOI: 10.1021/acs.iecr.2c01361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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He GH, Liu YL, Liu Y, Lu XB. Enantioselective Resolution Copolymerization of Racemic cis-Epoxides and Cyclic Anhydrides Mediated by Multichiral Bimetallic Chromium Complexes. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c00628] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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37
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Zhang K, Liu XF, Zhang WZ, Ren WM, Lu XB. Electrocarboxylation of N-Acylimines with Carbon Dioxide: Access to Substituted α-Amino Acids. Org Lett 2022; 24:3565-3569. [DOI: 10.1021/acs.orglett.2c01267] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Cui L, Liu Y, Ren BH, Lu XB. Preparation of Sequence-Controlled Polyester and Polycarbonate Materials via Epoxide Copolymerization Mediated by Trinuclear Co(III) Complexes. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c00501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Chao JY, Yue TJ, Ren BH, Gu GG, Lu XB, Ren WM. Controlled Disassembly of Elemental Sulfur: An Approach to the Precise Synthesis of Polydisulfides. Angew Chem Int Ed Engl 2022; 61:e202115950. [PMID: 35129257 DOI: 10.1002/anie.202115950] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Indexed: 01/08/2023]
Abstract
The usage of elemental sulfur (S8 ) for constructing sulfur-containing polymers is of great significance in terms of sulfur resource utilization or fabrication of high-performance polymers. Currently, the random disassembly of S8 hinders its direct use in the precise synthesis of sulfur-containing polymers. Herein, we provide an effective strategy for controlling the dismantlement of S8 to synthesize polydisulfides, a promising category of dynamic bonds containing polymers. In this strategy, the completely alternating copolymerization of one sulfur atom, which is orderly derived from S8 , with episulfides is achieved with MTBD (7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene) as catalyst and [PPN]SbF6 ([PPN]+ is bis(triphenylphosphine)iminium) as cocatalyst. Delightedly, the living- polymerization feature, and the good monomer compatibility allows for the access to diverse polydisulfides. Furthermore, the density functional theory (DFT) was employed to elaborate the copolymerization process.
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Zhang WW, Jia P, Lu XB, Chen XQ, Weng JH, Jia KT, Yi MS. Capsid protein from red-spotted grouper nervous necrosis virus induces incomplete autophagy by inactivating the HSP90ab1-AKT-MTOR pathway. Zool Res 2022; 43:98-110. [PMID: 34904422 PMCID: PMC8743256 DOI: 10.24272/j.issn.2095-8137.2021.249] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
As a highly important fish virus, nervous necrosis virus (NNV) has caused severe economic losses to the aquaculture industry worldwide. Autophagy, an evolutionarily conserved intracellular degradation process, is involved in the pathogenesis of several viruses. Although NNV can induce autophagy to facilitate infection in grouper fish spleen cells, how it initiates and mediates autophagy pathways during the initial stage of infection is still unclear. Here, we found that red-spotted grouper NNV (RGNNV) induced autophagosome formation in two fish cell lines at 1.5 and 3 h post infection, indicating that autophagy is activated upon entry of RGNNV. Moreover, autophagic detection showed that RGNNV entry induced incomplete autophagy by impairing the fusion of autophagosomes with lysosomes. Further investigation revealed that binding of the RGNNV capsid protein (CP) to the Lateolabrax japonicus heat shock protein HSP90ab1 (LjHSP90ab1), a cell surface receptor of RGNNV, contributed to RGNNV invasion-induced autophagy. Finally, we found that CP blocked the interaction of L. japonicus protein kinase B (AKT) with LjHSP90ab1 by competitively binding the NM domain of LjHSP90ab1 to inhibit the AKT-mechanistic target of the rapamycin (MTOR) pathway. This study provides novel insight into the relationship between NNV receptors and autophagy, which may help clarify the pathogenesis of NNV.
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Liao X, Cui FC, He JH, Ren WM, Lu XB, Zhang YT. Sustainable Approach for Synthesis and Completely Recycle of Cyclic CO 2-based Polycarbonates. Chem Sci 2022; 13:6283-6290. [PMID: 35733884 PMCID: PMC9159078 DOI: 10.1039/d2sc01387h] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 04/21/2022] [Indexed: 11/23/2022] Open
Abstract
It is highly desirable to reduce the environmental pollution related to the disposal of end-of-life plastics. Polycarbonates derived from the copolymerization of CO2 and epoxides have attracted much attention since they can enable CO2-fixation and furnish biorenewable and degradable polymeric materials. So far, only linear CO2-based polycarbonates have been reported and typically degraded to cyclic carbonates. Here we synthesize a homogeneous dinuclear methyl zinc catalyst ((BDI-ZnMe)2, 1) to rapidly copolymerize meso-CHO and CO2 into poly(cyclohexene carbonate) (PCHC) with an unprecedentedly cyclic structure. Moreover, in the presence of trace amounts of water, a heterogeneous multi-nuclear zinc catalyst ((BDI-(ZnMe2·xH2O))n, 2) is prepared and shows up to 99% selectivity towards the degradation of PCHC back to meso-CHO and CO2. This strategy not only achieves the first case of cyclic CO2-based polycarbonate but also realizes the complete chemical recycling of PCHC back to its monomers, representing closed-loop recycling of CO2-based polycarbonates. It is highly desirable to reduce the environmental pollution related to the disposal of end-of-life plastics.![]()
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Zhang YF, Lai WM, Xie S, Zhou H, Lu XB. Facile synthesis, structure and properties of CO2-sourced poly(thioether-co-carbonate)s containing acetyl pendants via thio-ene click polymerization. Polym Chem 2022. [DOI: 10.1039/d1py01477c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Synthetic transformation of CO2 into di- and trivinyl carbonates allows for photo-initiated thio-ene polymerization leading to sequence controlled poly(thioether-carbonate)s.
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43
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Li WB, Ren BH, Gu GG, Lu XB. Controlled Random Terpolymerization of
β
-Propiolactone, Epoxides, and CO
2
via
Regioselective Lactone Ring Opening. CCS CHEMISTRY 2022. [DOI: 10.31635/ccschem.021.202000728] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Yang JC, Yang J, Li WB, Lu XB, Liu Y. Carbonylative Polymerization of Epoxides Mediated by Tri-metallic Complexes: A Dual Catalysis Strategy for Synthesis of Biodegradable Polyhydroxyalkanoates. Angew Chem Int Ed Engl 2021; 61:e202116208. [PMID: 34964224 DOI: 10.1002/anie.202116208] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2021] [Indexed: 11/08/2022]
Abstract
Polyhydroxyalkanoates (PHAs) are a unique class of commercially manufactured biodegradable polyesters with properties suitable for partially substituting petroleum-based plastics. However, high costs and low volumes of production have restricted their application as commodity materials. In this study, tri-metallic complexes were developed for carbonylative polymerization of epoxides via a dual catalysis strategy, affording 17 products of novel PHAs with up to 38.2 kg/mol M n values. The polymerization proceeds in a sequential fashion, which entails the carbonylative ring expansion of epoxide to β -lactone and its subsequent ring-opening polymerization that occurs selectively at the O- alkyl bond via carboxylate species. The wide availability and structural diversity of epoxide monomers provide PHAs with various structures, excellent functionalities, and tunable properties. This study represents a rare example of the preparation of PHAs using epoxides and carbon monoxide as raw materials.
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Yang JC, Yang J, Li WB, Lu XB, Liu Y. Carbonylative Polymerization of Epoxides Mediated by Tri‐metallic Complexes: A Dual Catalysis Strategy for Synthesis of Biodegradable Polyhydroxyalkanoates. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202116208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Chen W, Zhou H, Ren BH, Ren WM, Lu XB. COS-triggered oxygen/sulfur exchange of isatins: chemoselective synthesis of functionalized isoindigos and spirothiopyrans via self-condensation and the thio-Diels-Alder reaction. Org Biomol Chem 2021; 20:678-685. [PMID: 34939627 DOI: 10.1039/d1ob02157e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Herein, we present the first organocatalytic oxygen/sulfur atom exchange reaction (O/S ER) of isatins by employing carbonyl sulfide (COS) as a novel sulfuring reagent under mild reaction conditions. 8-Diazabicyclo[5.4.0]undec-7-ene (DBU) exhibited excellent activity in this approach. Remarkably, the chemical transformations of in situ generated 3-thioisatins can be tuned via the judicious choice of reaction solvents in a one pot process, enabling the selective formation of either functionalized isoindigos in CH3CN via a self-condensation process or spirothiopyrans in DMSO in the presence of conjugated dienes via the thio-Diels-Alder reaction. Mechanistic studies with experimental and density functional theory approaches revealed that the O/S ER between isatins and COS results in the formation of 3-thioisatins as the key intermediates, which further undergo solvent-controlled transformations to generate isoindigos or spirothiopyrans, respectively. The easily-accessible substrates and operational simplicity make the process suitable for further exploration. The practicality of this transformation was demonstrated by the gram-scale synthesis of isoindigo-based drug molecules and donor-acceptor conjugated polymers.
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Zhou H, Zhang F, Wang R, Lai WM, Xie S, Ren WM, Lu XB. Facile Access to Functionalized Poly(thioether)s via Anionic Ring-Opening Decarboxylative Polymerization of COS-Sourced α-Alkylidene Cyclic Thiocarbonates. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c01475] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Chen SY, Pan RC, Liu Y, Lu XB. Bulky o-Phenylene-Bridged Bimetallic α-Diimine Ni(II) and Pd(II) Catalysts in Ethylene (Co)polymerization. Organometallics 2021. [DOI: 10.1021/acs.organomet.1c00374] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Li J, Wang MW, Liu Y, Ren WM, Lu XB. Photoinduced Reversible Semicrystalline-to-Amorphous State Transitions of Stereoregular Azopolyesters. Angew Chem Int Ed Engl 2021; 60:17898-17903. [PMID: 34129266 DOI: 10.1002/anie.202104750] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 06/03/2021] [Indexed: 11/09/2022]
Abstract
We report the synthesis of isotactic azobenzene-based polyesters (azopolyesters) with main-chain chirality via highly enantioselective resolution copolymerization of racemic azobenzene-containing epoxides with cyclic anhydrides. All polyesters with trans-azobenzene moieties were found to be semicrystalline materials with melting temperatures of 153-231 °C, while the corresponding isotactic cis-azopolyesters were amorphous. The azobenzene groups in the copolymers exhibited reversible trans-to-cis and cis-to-trans photoisomerization upon irradiation with light. This demonstrates that the crystallinity of isotactic azopolyesters can be manipulated via photoinduced reversible isomerization. In addition, mixing isotactic trans-polyesters with different enantiomeric configurations in a 1:1 mass ratio afforded crystalline stereocomplexes for which the crystalline behavior differed significantly from those of the component enantiomer. Also, photoinduced reversible transitions between semicrystalline and amorphous states were observed in various stereocomplexes of isotactic trans-azopolyesters, similar to the isotactic azopolyesters themselves.
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Chen SY, Pan RC, Chen M, Liu Y, Chen C, Lu XB. Synthesis of Nonalternating Polyketones Using Cationic Diphosphazane Monoxide-Palladium Complexes. J Am Chem Soc 2021; 143:10743-10750. [PMID: 34237217 DOI: 10.1021/jacs.1c04964] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Copolymerization of olefin with carbon monoxide has received considerable interest from both academia and industry, and the introduction of polar carbonyl group renders the resultant polyketones with excellent mechanical strength, crystallinity, photodegradability, hydrophilicity, surface, and barrier properties. However, most of the reported polyketones are difficult to be processed because of limited solubility in common solvents and high melting temperature (Tm ∼ 260 °C) resulting from the strictly alternative structure. Nonalternating copolymerization of ethylene with CO is a very promising method to circumvent the problem of processability of traditional perfectly alternating polyketone. In the contribution, the palladium coordinated diphosphazane monoxide substituted by strong electron-donating groups is discovered to be highly reactive for producing nonalternating polyketones, and up to 24.2% extra ethylene incorporation has lowered Tm values to 147 and 165 °C and further improved thermal stability (Td ∼ 339 °C) of the resultant materials. Our data demonstrates that cationic palladium complexes can also exhibit excellent reactivity and an unprecedented nonalternating degree in this copolymerization.
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