RESUMEN
Multicomponent reactions (MCRs), as a powerful one-pot combinatorial synthesis tool, have been recently applied to the synthesis of covalent organic frameworks (COFs). Compared with the thermally driven MCRs, the photocatalytic MCR-based COF synthesis has not yet been investigated. Herein, we first report the construction of COFs by a photocatalytic multicomponent reaction. Upon visible-light irradiation, a series of COFs with excellent crystallinity, stability, and permanent porosity are successfully synthesized via photoredox-catalyzed multicomponent Petasis reaction under ambient conditions. Additionally, the obtained Cy-N3-COF exhibits excellent photoactivity and recyclability for the visible-light-driven oxidative hydroxylation of arylboronic acids. The concept of photocatalytic multicomponent polymerization not only enriches the methodology for COF synthesis but also opens a new avenue for the construction of COFs that might not be possible with the existing synthetic methods based on thermally driven MCRs.
RESUMEN
A fully sp2-carbon conjugated COF (Py-FTP-COF) was designed and synthesized, exhibiting excellent hydrogen evolution rate of 5.22 mmol g-1 h-1. More importantly, in situ hydrogenation of nitroarenes under visible-light irradiation without any additional hydrogen source was successfully accomplished for the first time over COF-based materials.
RESUMEN
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.
RESUMEN
We demonstrate herein a newly designed benzothiadiazole-based covalent organic framework through an imine linkage with high crystallinity, excellent chemical stability and significant light absorption ability, which was further applied as a high-performance platform for efficient visible-light driven hydrogen evolution.
RESUMEN
Cancer nanomedicine is one of the most promising domains that has emerged in the continuing search for cancer diagnosis and treatment. The rapid development of nanomaterials and nanotechnology provide a vast array of materials for use in cancer nanomedicine. Among the various nanomaterials, covalent organic frameworks (COFs) are becoming an attractive class of upstarts owing to their high crystallinity, structural regularity, inherent porosity, extensive functionality, design flexibility, and good biocompatibility. In this comprehensive review, recent developments and key achievements of COFs are provided, including their structural design, synthesis methods, nanocrystallization, and functionalization strategies. Subsequently, a systematic overview of the potential oncotherapy applications achieved till date in the fast-growing field of COFs is provided with the aim to inspire further contributions and developments to this nascent but promising field. Finally, development opportunities, critical challenges, and some personal perspectives for COF-based cancer therapeutics are presented.
RESUMEN
In this work, we present the successful synthesis of a series of sulfonic acid functionalized mixed-linker metal-organic frameworks (MOFs) having the DUT-4 topology by using different ratios of 2,6-naphthalenedicarboxylic acid (H2-NDC) and 4,8-disulfonaphthalene-2,6-dicarboxylic acid (H2-NDC-2SO3H) in one-pot reactions. The obtained materials were fully characterized and their CO2 adsorption properties at low and high pressures were studied and compared with those of the pristine DUT-4 material. Generally, the CO2 adsorption capacities range from 3.28 and 1.36 mmol g-1 for DUT-4 to 1.54 and 0.78 mmol g-1 for DUT-4-SO3H (50) up to 1 bar at 273 K and 303 K, respectively. Computational calculations corroborated the structural changes of the material in function of the loading of sulfonic acid groups. Furthermore, due to the strong Brønsted acid character, the resulting sulfonic acid based MOF material was evaluated as a catalyst for the ring opening of styrene oxide with methanol as a nucleophile under mild conditions, showing almost full conversion (99%) after 5 hours of reaction. A hot filtration experiment demonstrated that the catalysis occurred heterogeneously and the catalyst could be recovered and reused for multiple runs without significant loss in activity and crystallinity.
RESUMEN
The title compound, 3C(14)H(12)N(2)O(2)·C(3)H(7)NO, was synthesized by reaction of benzoyl chloride with hydrazine hydrate under microwave irradition. The asymmetric unit comprises three 1,2-dibenzoyl-hydrazine mol-ecules and one dimethyl-formamide mol-ecule. The 1,2-dibenzoyl-hydrazine mol-ecules are linked by pairs of N-Hâ¯O hydrogen bonds into chains propagating along [010].
