A general and efficient organocatalytic asymmetric polymerization approach for the synthesis of chiral covalent organic frameworks (CCOFs) has been developed. With a chiral 2‐methylpyrrolidine ...catalyst, a series of tris(N‐salicylideneamine)‐derived β‐ketoenamine‐CCOFs are directly constructed from prochiral aldehyde‐ and primary amine‐monomers. The adopted aminocatalytic asymmetric Schiff‐base condensation herein is performed under ambient conditions with clear green synthetic advantages over the conventional acid‐catalysed solvothermal methods. The obtained β‐ketoenamine‐CCOFs can be further metalated by a solid‐state coordination approach, and the resulting CuII@CCOFs can highly promote an asymmetric A3‐coupling reaction. Specifically, a CuII@CCOF@chitosan aerogel was fabricated as a highly efficient fixed‐bed model reactor for scaled‐up catalysis. The concept of aminocatalytic asymmetric polymerization might open a new way for constructing the CCOFs via asymmetric organocatalysis.
A new and general organocatalytic asymmetric polymerization approach for the chiral covalent organic framework (CCOF) synthesis under ambient conditions is presented. The metalated CCOF can be further shaped into a fixed‐bed reactor by incorporation with ecofriendly and low‐cost chitosan to realize the scaled‐up catalytic asymmetric A3‐coupling reaction in a green and facile way.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Photothermal therapy in the second near-infrared window (NIR-II, 1000-1700 nm) exhibits a significant advantage over the first near-infrared window (NIR-I, 650-950 nm) in terms of both maximum ...permissible exposure (MPE) and penetration depth. However, the thus far reported NIR-II photothermal agents (PTAs) have been focused just on inorganic semiconducting and organic polymeric semiconducting nanoparticles. Herein a novel cruciform phthalocyanine pentad was designed, synthesized, and characterized for the first time. The water-soluble nanoparticles (Zn
4
-H
2
Pc/DP NPs) assembled from this single molecular material with the help of DSPE-PEG
2000
-OCH
3
exhibit characteristic absorption in the NIR-II region at 1064 nm with a large extinction coefficient of 52 L g
−1
cm
−1
, high photothermal conversion efficiency of 58.3%, and intense photoacoustic signal. Moreover, both
in vitro
and
in vivo
studies reveal the good biocompatibility and notable tumor ablation ability of Zn
4
-H
2
Pc/DP NPs under 1064 nm laser irradiation. Theoretical density functional theory calculations interpret the two-dimensional compressional wave energy-dissipation pathway over the broad saddle curved framework of the cruciform conjugated phthalocyanine pentad, rationalizing the efficient photothermal properties of corresponding Zn
4
-H
2
Pc/DP NPs in the NIR-II window.
The first molecular material-based PTA for the NIR-II photothermal therapy with high PCE of 58.3% was reported. The Zn
4
-H
2
Pc/DP NPs reveal good biocompatibility and notable tumor ablation ability in 1064 nm.
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IJS, KILJ, NUK, UL, UM, UPUK
Stimulus-responsive biodegradable nanocarriers with tumor-selective targeted drug delivery are critical for cancer therapy. Herein, we report for the first time a redox-responsive disulfide-linked ...porphyrin covalent organic framework (COF) that can be nanocrystallized by glutathione (GSH)-triggered biodegradation. After loading 5-fluorouracil (5-Fu), the generated nanoscale COF-based multifunctional nanoagent can be further effectively dissociated by endogenous GSH in tumor cells, releasing 5-Fu efficiently to achieve selective chemotherapy on tumor cells. Together with the GSH depletion-enhanced photodynamic therapy (PDT), an ideal synergistic tumor therapy for MCF-7 breast cancer
via
ferroptosis is achieved. In this research, the therapeutic efficacy was significantly improved in terms of enhanced combined anti-tumor efficiency and reduced side effects by responding to significant abnormalities such as high concentrations of GSH in the tumor microenvironment (TME).
Stimulus-responsive biodegradable nanocarriers with tumor-selective targeted drug delivery are critical for cancer therapy.
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IJS, KILJ, NUK, UL, UM, UPUK
A Pd NP-loaded and paraffin-chain quaternary ammonium salt-decorated covalent organic framework, Pd@COF-QA , and its chitosan aerogel-based continuous flow-through reactor, which could be an ...excellent phase transfer catalyst to promote the aqueous Suzuki–Miyaura coupling reaction, is reported.
Covalent organic frameworks (COFs) have recently drawn intense attention due to their potential applications in photocatalysis. Herein, we report a multifunctional COF which consists of ...triphenylamine (TPA) and 2,2′‐bipyridine (2, 2′‐bipy) entities. The obtained TAPA−BPy−COF is a heterogeneous photocatalyst and can efficiently catalyze the oxidative coupling of thiols to disulfides. In addition, TAPA−BPy−COF can be further metalated by Pd(II) via 2,2′‐bipy−metal coordination. The generated Pd@TAPA−BPy−COF can highly promote photocatalytic synthesis of 3‐cyanopyridines via cascade addition/cyclization of arylboronic acids with γ‐ketodinitriles in heterogeneous way. This work has demonstrated the way for the rational design and preparation of more efficient photoactive COFs for photocatalysis.
A photoactive TAPA−BPy−COF and its metalated Pd@TAPA−BPy−COF, which can both serve as the efficient reusable photocatalysts for photocatalytic applications, are reported.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Herein, we report an organometallic framework (OMF) generated from a divergent tridentate arylisocyanide ligand and PdI
2
under solvothermal conditions. The obtained Pd-C bond-connected ...two-dimensional
Pd-OMF
was crystalline and porous. Moreover, it could be a highly active catalyst to promote the Suzuki-Miyaura cross-coupling reaction in a heterogeneous manner.
A Pd-C-bond-connected organometallic framework and its catalytic activity for the Suzuki-Miyaura cross-coupling reaction were reported.
Herein, we report the first reactive oxygen species (ROS)-responsive dithioketal-linked covalent organic framework (COF) for synergetic chemotherapy and photodynamic therapy (PDT) of cancer. The ...singlet oxygen (
1
O
2
)-responsive COF dissociation and DC_AC50 drug release complement and reinforce each other to allow an efficient combination of PDT and chemotherapy.
Herein, we report the first reactive oxygen species (ROS)-responsive dithioketal-linked covalent organic framework (COF) for synergetic chemotherapy and photodynamic therapy (PDT) of cancer.
A new composite Au@Cu(II)-MOF catalyst has been synthesized via solution impregnation and full characterized by HRTEM, SEM-EDS, XRD, gas adsorption–desorption, XPS, and ICP analysis. It has been ...shown here that the Cu(II)-framework can be a useful platform to stabilize and support gold nanoparticles (Au NPs). The obtained Au@Cu(II)-MOF exhibits a bifunctional catalytic behavior and is able to promote selective aerobic benzyl alcohol oxidation–Knoevenagel condensation in a stepwise way.
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IJS, KILJ, NUK, PNG, UL, UM
Covalent organic frameworks (COFs), featuring semiconductor-like behavior, have recently garnered widespread interest for applications in photocatalysis by virtue of their well-defined and tailorable ...porous structures, high surface areas and excellent chemical stability. A facile strategy for designing COFs exerting efficient charge transfer and separation as well as suppressing charge carrier recombination is the precise integration of electron-donating and electron-withdrawing moieties to form long-range ordered donor-acceptor (D-A) type structures. In this work, we rationally designed and synthesized a novel imine-linked COF (
DABT-Py-COF
) by the condensation of a newly designed D-A-D type monomer of 4,4′,4′′,4′′′-(benzo
c
1,2,5thiadiazole-4,7-diylbis(9,9-dimethyl-9,10-dihydroacridine-10,2,7-triyl))tetrabenzaldehyde and 1,3,6,8-tetrakis(4-aminophenyl)pyrene under solvothermal conditions. Remarkably, the obtained
DABT-Py-COF
exhibited outstanding and steady hydrogen production with a maximum hydrogen evolution rate (HER) of 5458 μmol g
−1
h
−1
under visible-light irradiation (AM 1.5). This work has paved the way for the rational design and preparation of more efficient D-A type COFs for photocatalysis.
Derived from a D-A-D motif monomer, a novel COF was designed and synthesized, which exhibited excellent efficiency for hydrogen evolution from water under visible-light irradiation as a photocatalyst.
A benzodifuran-based donor-acceptor covalent organic framework was synthesized and employed for efficient simulated sunlight-driven photocatalytic hydrogen evolution from water, which exhibited a ...superior and steady hydrogen evolution rate of 1390 μmol g
−1
h
−1
and an outstanding apparent quantum yield (AQY) of 7.8% was obtained at 420 nm.
A benzodifuran-functionalized donor-acceptor covalent organic framework was synthesized and employed for efficient sunlight-driven hydrogen evolution from water.
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