Covalent organic frameworks (COFs) featuring chirality, stability, and function are of both fundamental and practical interest, but are yet challenging to achieve. Here we reported the metal-directed synthesis of two chiral COFs (CCOFs) by imine-condensations of enantiopure 1,2-diaminocyclohexane with C-symmetric trisalicylaldehydes having one or zero 3-tert-butyl group. Powder X-ray diffraction and modeling studies, together with pore size distribution analysis demonstrate that the Zn(salen)-based CCOFs possess a two-dimensional hexagonal grid network with AA stacking. Dramatic enhancement in the chemical stability toward acidic (1 M HCl) and basic (9 M NaOH) conditions was observed for the COF incorporated with tert-butyl groups on the pore walls compared to the nonalkylated analog. The Zn(salen) modules in the CCOFs allow for installing multivariate metals into the frameworks by postsynthetic metal exchange. The exchanged CCOFs maintain high crystallinity and porosity and can serve as efficient and recyclable heterogeneous catalysts for asymmetric cyanation of aldehydes, Diels-Alder reaction, alkene epoxidation, epoxide ring-opening, and related sequential reactions with up to 97% ee.
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http://dx.doi.org/10.1021/jacs.7b04008 | DOI Listing |
Inorg Chem
January 2025
Henan Key Laboratory of Polyoxometalate Chemistry, College of Chemistry and Molecular Sciences, Henan University, Kaifeng, Henan 475004, P. R. China.
Three cases of aminobenzoic acid hybrid polyoxotungstates, Na(HO)[(HPWO) (OCCHNH)]·7HO (), K(HO)[(AsWO)(OCCHNH)]·4HO (), and [(HN(CH)]Na(HO)[(SbWO) (OCCHNH)]·7HO (), were successfully synthesized. This is the first report of the successful assembly of the hexanuclear {XW} (X = HP, As, or Sb) clusters and organic carboxylic acid (para aminobenzoic acid) ligands. All three hybrids feature a common {XW} unit composed of a six-membered {WO} octahedral ring capped by one {XO} trigonal pyramid.
View Article and Find Full Text PDFRSC Adv
January 2025
Department of Chemistry, Faculty of Science, University of Maragheh P.O Box 55181-83111 Maragheh Iran.
In this study, we present the design, synthesis, and utilization of a covalent triazine framework (CTF) formed by the condensation of , , -tris(4-(aminomethyl)benzyl)-1,3,5-triazine-2,4,6-triamine and 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine on which silica is immobilized (TPT-TAT/silica) as an innovative catalyst for porphyrins synthesis. Under solvothermal conditions, the condensation of triamine and trialdehyde precursors led to the formation of a covalent triazine framework (CTF) with a high nitrogen content. The resulting CTF is characterized by its extensive porosity and elevated nitrogen levels, which are critical for the creation of catalytic active sites.
View Article and Find Full Text PDFDalton Trans
January 2025
Univ. Bourgogne Europe, CNRS, ICMUB (UMR 6302) Institut de Chimie Moléculaire de l'Université de Bourgogne, 9, Avenue Alain Savary, 21 000 Dijon, France.
We report herein the synthesis and full spectroscopic characterization of two AB-corrole phosphonic acids. Thanks to the presence of a phosphonic acid functional group at the 10--position, the corroles were covalently linked to the hexanuclear Zr clusters of a PCN-222 metal-organic framework (MOF). After the insertion of cobalt into the corrole macrocycle, the metal complexes are able to bind small volatile molecules such as carbon monoxide (CO).
View Article and Find Full Text PDFChem Commun (Camb)
January 2025
Sardar Vallabhbhai National Institute of Technology, Ichchanath, Surat-395 007, Gujarat, India.
The advancement in materials chemistry promoted the growth of energy storage systems such as capacitors, supercapacitors and batteries. Covalent organic frameworks and nanomaterials have significantly improved the performance of various energy storage systems. Because of the unique properties of these materials, like high surface area, tunable architectures, and enhanced conductivity, researchers have developed effective and durable energy storage solutions for multiple applications.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Sun Yat-Sen University, School of Chemistry, 135 Xingang West, 510275, Guangzhou, CHINA.
Integrating enzymes with reticular frameworks offers promising avenues for access to functionally tailorable biocatalysis. This Minireview explores recent advances in enzyme-reticular frameworks hybrid biocomposites, focusing on the utilization of porous reticular frameworks, including metal-organic frameworks, covalent-organic frameworks, and hydrogen-bonded organic frameworks, to regulate the reactivity of an enzyme encapsulated inside mainly by pore infiltration and in situ encapsulation strategies. We highlight how pore engineering and host-guest interfacial interactions within reticular frameworks create tailored microenvironments that substantially impact the mass transfer and enzyme's conformation, leading to biocatalytic rate enhancement, or imparting enzyme with non-native biocatalytic functions including substrate-selectivity and new activity.
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