Vinylene-Linked Covalent Organic Frameworks by Base-Catalyzed Aldol Condensation

Two 2D covalent organic frameworks (COFs) linked by vinylene (−CH=CH−) groups (V‐COF‐1 and V‐COF‐2) are synthesized by exploiting the electron deficient nature of the aromatic s‐triazine unit of C3‐symmetric 2,4,6‐trimethyl‐s‐triazine (TMT). The acidic terminal methyl hydrogens of TMT can easily be abstracted by a base, resulting in a stabilized carbanion, which further undergoes aldol condensation with multitopic aryl aldehydes to be reticulated into extended crystalline frameworks (V‐COFs). Both V‐COF‐1 (with terepthalaldehyde (TA)) and V‐COF‐2 (with 1,3,5‐tris(p‐formylphenyl)benzene (TFPB)) are polycrystalline and exhibit permanent porosity and BET surface areas of 1341 m2 g−1 and 627 m2 g−1, respectively. Owing to the close proximity (3.52 Å) of the pre‐organized vinylene linkages within adjacent 2D layers stacked in eclipsed fashion, [2+2] photo‐cycloadditon in V‐COF‐1 formed covalent crosslinks between the COF layers.TU Berlin, Open-Access-Mittel - 2019DFG, 390540038, EXC 2008: UniSysCa

Strongly Reducing (Diarylamino)benzene-Based Covalent Organic Framework for Metal-Free Visible Light Photocatalytic H2O2 Generation

Photocatalytic reduction of molecular oxygen is a promising route toward sustainable production of hydrogen peroxide (H2O2). This challenging process requires photoactive semiconductors enabling solar energy driven generation and separation of electrons and holes with high charge transfer kinetics. Covalent organic frameworks (COFs) are an emerging class of photoactive semiconductors, tunable at a molecular level for high charge carrier generation and transfer. Herein, we report two newly designed two-dimensional COFs based on a (diarylamino)benzene linker that form a Kagome (kgm) lattice and show strong visible light absorption. Their high crystallinity and large surface areas (up to 1165 m(2)center dot g(-1)) allow efficient charge transfer and diffusion. The diarylamine (donor) unit promotes strong reduction properties, enabling these COFs to efficiently reduce oxygen to form H2O2. Overall, the use of a metal-free, recyclable photocatalytic system allows efficient photocatalytic solar transformations.DFG, 390540038, EXC 2008: Unifying Systems in Catalysis "UniSysCat"EC/H2020/665501/EU/[PEGASUS]², giving wings to your career./PEGASUS-2EC/H2020/834134/EU/Water Forced in Hydrophobic Nano-Confinement: Tunable Solvent System/WATUSOEC/H2020/647755/EU/First principle molecular dynamics simulations for complex chemical transformations in nanoporous materials/DYNPO

Metal-assisted and solvent-mediated synthesis of two-dimensional triazine structures on gram scale

We thank the German Science Foundation (DFG) for financial support within the grants SFB 765 and SFB 658. M.F.G. and J.P.R. also acknowledge the support of the Cluster of Excellence “Matters of Activity. Image Space Material” funded by the DFG under Germany’s Excellence Strategy EXC 2025-390648296. Furthermore, A.T. acknowledges the DFG for funding within the project TH 1463/12-1. We thank Dr. Andreas Schäfer and Maiko Schulze for solid NMR experiments and we appreciate the effort of Vahid Ahmadi Soureshjani in MALDI-TOF experiments. We acknowledge M. Eng. Jörg M. Stockmann for operating the XPS instrument at the BAM and Prof. Stephanie Reich and Dr. Antonio Setaro for fruitful discussions. 2DTs-HRTEM and -EELS studies were conducted at the Laboratorio de Microscopias Avanzadas, Instituto de Nanociencia de Aragon, Universidad de Zaragoza, Spain. R.A. gratefully acknowledges the support from the Spanish Ministry of Economy and Competitiveness (MINECO) through project grant MAT2016-79776-P (AEI/FEDER, UE) and from the European Union H2020 programs ETN projects “Graphene Flagship” (785219 and 881603), FLAG-ERA - Graphene (MICINN) GATES (PCI2018-093137) and “ESTEEM3” (823717).Peer reviewe

Covalent organic frameworks (COFs) for electrochemical applications

Covalent organic frameworks are a class of extended crystalline organic materials that possess unique architectures with high surface areas and tuneable pore sizes. Since the first discovery of the topological frameworks in 2005, COFs have been applied as promising materials in diverse areas such as separation and purification, sensing or catalysis. Considering the need for renewable and clean energy production, many research efforts have recently focused on the application of porous materials for electrochemical energy storage and conversion. In this respect, considerable efforts have been devoted to the design and synthesis of COF-based materials for electrochemical applications, including electrodes and membranes for fuel cells, supercapacitors and batteries. This review article highlights the design principles and strategies for the synthesis of COFs with a special focus on their potential for electrochemical applications. Recently suggested hybrid COF materials or COFs with hierarchical porosity will be discussed, which can alleviate the most challenging drawback of COFs for these applications. Finally, the major challenges and future trends of COF materials in electrochemical applications are outlined.DFG, 390540038, EXC 2008: Unifying Systems in Catalysis "UniSysCat"TU Berlin, Open-Access-Mittel – 202

Correction to Porous Nitrogen Rich Cadmium-Tetrazolate Based Metal Organic Framework (MOF) for H₂ and CO₂ Uptake

Correction to Porous Nitrogen Rich Cadmium-Tetrazolate Based Metal Organic Framework (MOF) for H₂ and CO₂ Uptak

Correction to Porous Nitrogen Rich Cadmium-Tetrazolate Based Metal Organic Framework (MOF) for H₂ and CO₂ Uptake

Correction to Porous Nitrogen Rich Cadmium-Tetrazolate Based Metal Organic Framework (MOF) for H₂ and CO₂ Uptak

Functionalization and Isoreticulation in a Series of Metal–Organic Frameworks Derived from Pyridinecarboxylates

The partially fluorinated metal–organic frameworks (F-MOFs) have been constructed from 3-fluoro-4-pyridinecarboxylic acid and <i>trans</i>-3-fluoro-4-pyridineacrylic acid linkers using Mn²⁺, Co²⁺, and Cd²⁺ metals via the solvothermal method, which show isostructural isomerism with their nonfluorinated counterparts synthesized using 4-pyridinecarboxylic acid and <i>trans</i>-4-pyridineacrylic acid, respectively. The simultaneous effect of partial fluorination and isoreticulation on structure and H₂ adsorption has been studied systematically in isostructural nonfluorinated and partially fluorinated MOFs, which shows that the increment in the hydrogen uptake properties in F-MOFs is not a universal phenomenon but is rather system-specific and changes from one system to another

Comprehensive Study on Mutual Interplay of Multiple V‑Shaped Ligands on the Helical Nature of a Series of Coordination Polymers and Their Properties

V-shaped ligands are commonly used for helical coordination polymer synthesis. However, employment of multiple V-shaped ligands does not always lead to a helical network. The mutual interplay of two V-shaped ligands, which is neither easily predictable nor well documented, plays a major role directing the self-assembly of the resultant network. We report here the construction of a series of novel coordination polymers {[Ni­(OBA)­(H₂MDP)­(H₂O)]·(DMF)₃}_<i>n</i> (<b>1</b>),{[Ni­(FBA)­(H₂MDP)]·(H₂O)₃·(DMF)}_<i>n</i> (<b>2</b>),{[Ni₂(IPA)₂(H₂MDP)₂(H₂O)]·(H₂O)­(DMF)}_<i>n</i> (<b>3</b>),{[Ni­(ADA)­(H2MDP)]·(MeOH)}_<i>n</i> (<b>4</b>),[Ni­(TNBA)­(H₂MDP)₂]_<i>n</i> (<b>5</b>), {[Ni­(PPA)­(H₂MDP)₂]·(H₂O)₂}_<i>n</i> (<b>6</b>), {[Ni­(HDPA)₂(H₂MDP)₂]}_<i>n</i> (<b>7</b>), and [Ni­(SBA)­(H₂MDP)]_<i>n</i> (<b>8</b>) {where H₂OBA = 4,4′<b>-</b>oxybis­(benzoic acid), H₂FBA = 4,4′-(hexafluoroisopropylidene)­bis­(benzoic acid), H₂IPA = isophthalic acid, H₂ADA =1,3-adamantanediacetic acid, H₂TNBA = 5,5′-dithiobis­(2-nitrobenzoic acid), H₂PPA 1,4-phenylenedipropionic acid, H₂DPA = diphenic acid H₂SBA= 4,4′-sulfonyldibenzoic acid} using a combination of mixed V-shaped ligands. The deployment of bent ligands yields a rich variety of network topologies with various helical motifs comprising both the linkers and the individual one. A detailed gas sorption study of porous networks, as evident from the presence of distinct nanoporous voids and channels inside the structures, is also investigated. Furthermore, chirality associated with helical networks and their role as potential functional materials are verified by solid state circular dichroism spectra

Comprehensive Study on Mutual Interplay of Multiple V‑Shaped Ligands on the Helical Nature of a Series of Coordination Polymers and Their Properties

V-shaped ligands are commonly used for helical coordination polymer synthesis. However, employment of multiple V-shaped ligands does not always lead to a helical network. The mutual interplay of two V-shaped ligands, which is neither easily predictable nor well documented, plays a major role directing the self-assembly of the resultant network. We report here the construction of a series of novel coordination polymers {[Ni­(OBA)­(H₂MDP)­(H₂O)]·(DMF)₃}_<i>n</i> (<b>1</b>),{[Ni­(FBA)­(H₂MDP)]·(H₂O)₃·(DMF)}_<i>n</i> (<b>2</b>),{[Ni₂(IPA)₂(H₂MDP)₂(H₂O)]·(H₂O)­(DMF)}_<i>n</i> (<b>3</b>),{[Ni­(ADA)­(H2MDP)]·(MeOH)}_<i>n</i> (<b>4</b>),[Ni­(TNBA)­(H₂MDP)₂]_<i>n</i> (<b>5</b>), {[Ni­(PPA)­(H₂MDP)₂]·(H₂O)₂}_<i>n</i> (<b>6</b>), {[Ni­(HDPA)₂(H₂MDP)₂]}_<i>n</i> (<b>7</b>), and [Ni­(SBA)­(H₂MDP)]_<i>n</i> (<b>8</b>) {where H₂OBA = 4,4′<b>-</b>oxybis­(benzoic acid), H₂FBA = 4,4′-(hexafluoroisopropylidene)­bis­(benzoic acid), H₂IPA = isophthalic acid, H₂ADA =1,3-adamantanediacetic acid, H₂TNBA = 5,5′-dithiobis­(2-nitrobenzoic acid), H₂PPA 1,4-phenylenedipropionic acid, H₂DPA = diphenic acid H₂SBA= 4,4′-sulfonyldibenzoic acid} using a combination of mixed V-shaped ligands. The deployment of bent ligands yields a rich variety of network topologies with various helical motifs comprising both the linkers and the individual one. A detailed gas sorption study of porous networks, as evident from the presence of distinct nanoporous voids and channels inside the structures, is also investigated. Furthermore, chirality associated with helical networks and their role as potential functional materials are verified by solid state circular dichroism spectra

Comprehensive Study on Mutual Interplay of Multiple V‑Shaped Ligands on the Helical Nature of a Series of Coordination Polymers and Their Properties

V-shaped ligands are commonly used for helical coordination polymer synthesis. However, employment of multiple V-shaped ligands does not always lead to a helical network. The mutual interplay of two V-shaped ligands, which is neither easily predictable nor well documented, plays a major role directing the self-assembly of the resultant network. We report here the construction of a series of novel coordination polymers {[Ni­(OBA)­(H₂MDP)­(H₂O)]·(DMF)₃}_<i>n</i> (<b>1</b>),{[Ni­(FBA)­(H₂MDP)]·(H₂O)₃·(DMF)}_<i>n</i> (<b>2</b>),{[Ni₂(IPA)₂(H₂MDP)₂(H₂O)]·(H₂O)­(DMF)}_<i>n</i> (<b>3</b>),{[Ni­(ADA)­(H2MDP)]·(MeOH)}_<i>n</i> (<b>4</b>),[Ni­(TNBA)­(H₂MDP)₂]_<i>n</i> (<b>5</b>), {[Ni­(PPA)­(H₂MDP)₂]·(H₂O)₂}_<i>n</i> (<b>6</b>), {[Ni­(HDPA)₂(H₂MDP)₂]}_<i>n</i> (<b>7</b>), and [Ni­(SBA)­(H₂MDP)]_<i>n</i> (<b>8</b>) {where H₂OBA = 4,4′<b>-</b>oxybis­(benzoic acid), H₂FBA = 4,4′-(hexafluoroisopropylidene)­bis­(benzoic acid), H₂IPA = isophthalic acid, H₂ADA =1,3-adamantanediacetic acid, H₂TNBA = 5,5′-dithiobis­(2-nitrobenzoic acid), H₂PPA 1,4-phenylenedipropionic acid, H₂DPA = diphenic acid H₂SBA= 4,4′-sulfonyldibenzoic acid} using a combination of mixed V-shaped ligands. The deployment of bent ligands yields a rich variety of network topologies with various helical motifs comprising both the linkers and the individual one. A detailed gas sorption study of porous networks, as evident from the presence of distinct nanoporous voids and channels inside the structures, is also investigated. Furthermore, chirality associated with helical networks and their role as potential functional materials are verified by solid state circular dichroism spectra