The production of high‐value chemicals by single‐atom catalysis is an attractive proposition for industry owing to its remarkable selectivity. Successful demonstrations to date are mostly based on ...gas‐phase reactions, and reports on liquid‐phase catalysis are relatively sparse owing to the insufficient activation of reactants by single‐atom catalysts (SACs), as well as, their instability in solution. Here, mechanically strong, hierarchically porous carbon plates are developed for the immobilization of SACs to enhance catalytic activity and stability. The carbon‐based SACs exhibit excellent activity and selectivity (≈68%) for the synthesis of substituted quinolines by a three‐component oxidative cyclization, affording a wide assortment of quinolines (23 examples) from anilines and acetophenones feedstock in an efficient, atom‐economical manner. Particularly, a Cavosonstat derivative can be synthesized through a one‐step, Fe1‐catalyzed cyclization instead of traditional Suzuki coupling. The strategy is also applicable to the deuteration of quinolines at the fourth position, which is challenging by conventional methods. The synthetic utility of the carbon‐based SAC, together with its reusability and scalability, renders it promising for industrial scale catalysis.
Iron single‐atom catalysts are developed for three‐component oxidative cyclization, affording a wide assortment of multifunctional quinolines and their deuterated derivatives (23 examples including Cavosonstat derivatives) from feedstock anilines and acetophenones.
•Various analytical techniques were used to characterize the modification of TSP with SnCl2.•Efficient synthesis of xanthene and xanthenone derivatives.•Reusable catalyst for at least for 5 runs.•The ...reactions were performed under mild and green conditions.
A simple method was developed for preparing tin (II) chloride-triple superphosphate. The material was thoroughly characterized using various techniques, including transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), thermogravimetric analysis (TGA), and Brunauer–Emmett–Teller (BET) analysis. XRD analysis, BET, and SEM images indicated that the catalyst exhibited a crystalline structure and had particle sizes ranging from 21 to 23 nm. The catalytic performance was evaluated by conducting multicomponent one-pot condensation reactions. Specifically, the condensation of 2-naphthol with aldehydes and dimedone was conducted to produce 12-aryl(alkyl)-8,9,10,12 tetrahydrobenzo axanthen-11-one derivatives, and the condensation of 2-naphthol with aldehydes was performed to synthesize 14-aryl(alkyl)-14H-dibenzo a,jxanthene derivatives. The acidic sites of the catalyst were determined using pyridine FTIR spectroscopy. The studies revealed that this catalyst system exhibited excellent performance, resulting in high product yields (88–96%) and reduced reaction times (12–20 min). The catalyst demonstrated high catalytic activity, good reusability, and a simple preparation method, thereby showing promise for potential industrial-scale applications.
A facile and metal-free visible-light-enabled three-component reaction of quinoxalin-2(1H)-ones, alkenes and CF3SO2Na has been developed under air at room temperature.
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A facile and ...metal-free visible-light-enabled three-component reaction of quinoxalin-2(1H)-ones, alkenes and CF3SO2Na has been developed under air at room temperature. This photocatalytic tandem reaction using 4CzIPN as the photocatalyst and air as the green oxidant, provides a mild and environmentally friendly approach to access a series of 3-trifluoroalkylated quinoxalin-2(1H)-ones.
A copper-catalyzed three-component reaction of cyclobutanone oxime esters and 1,3-enynes in the presence of TMSCN or TMSCF3 has been developed. This mild protocol enjoys a broad substrate scope ...tolerating many functional groups, providing a facile access to 1,7-double-functionalized allenes, which are difficult to prepare. The allenyl nitrile products may be easily transformed into allenoic acid derivatives and stereodefined tetrasubstituted alkenes, demonstrating their potentials as platform molecules in synthesis. A mechanism has been proposed on the basis of mechanistic studies.
The reaction of aldehydes, amines and alcohols usually leads to a series of equilibria from which isolation of one product is difficult to achieve. We have found that this three‐component reaction ...can be controlled and directed in an exclusive manner toward the formation of the hemiaminal ether. A series of 33 hemiaminal ethers has been obtained in high yields, from different aldehydes, amines and alcohols, under very mild conditions just with molecular sieves as promoter.
Covalent adaptable networks (CANs) have recently received extensive interests due to their reprocessability and repairability. Rethinking the libraries of the published CANs, most of them are ...fabricated by one/two‐component reactions and few cases utilize multi‐component reactions to construct CANs while multi‐component reactions are conductive to tailoring the properties of polymers due to their structural designability and flexible choice of raw materials. A novel kind of dynamic covalent bond named aminoesterenamide is presented through three‐component reaction between acetoacetyl, amine and isocyanate. Aminoesterenamide exhibits thermal reversibility through dissociating into vinylogous urethane and isocyanate. When it is used to prepare CANs, the synthesized polymer networks can be reprocessed many times via the exchange reaction between aminoesterenamides. Moreover, the forming of aminoesterenamide involving three starting components imparts CANs with great freedom to tailor their properties. Therefore, the authors believe this method that utilizes three‐component reaction to fabricate CANs would bring new stories and perspectives to the exploration of new types of CANs.
Covalent adaptable networks (CANs) represent a broad class of polymer networks with dynamic covalent bonds (DCBs) embedded in the cross‐linked structure, enabling recyclability. Most of DCBs are fabricated by one/two‐component reactions. To enrich the method of fabricating DCBs, a novel kind of DCB named aminoesterenamide is presented via three‐component reaction. The aminoesterenamide‐containing CANs exhibit easily tailored structures and properties besides reprocessability.
In the present work, a new protocol was introduced for the preparation of an efficient hybrid nanocatalyst ZnS‐ZnFe2O4 via the co‐precipitation method as well as its application in the synthesis of ...2,4,5‐triaryl‐1H‐imidazoles derivatives starting from various aromatic aldehydes, benzil and ammonium acetate under ultrasonic irradiation in ethanol. ZnS‐ZnFe2O4 was characterized by Fourier transform infrared (FT‐IR) spectroscopy, energy‐dispersive X‐ray spectroscopy (EDS) analysis, scanning electron microscopy (SEM) image, X‐ray diffraction (XRD) pattern and vibrating sample magnetometer (VSM) curve. This method has advantages such as high efficiency of the heterogeneous catalyst, the use of environmentally‐friendly solvent, high yields, short reaction times and easy isolation of the products and chromatography‐free purification. Our outcomes illustrated that the present nanocatalyst with nearly spherical and Cauliflower‐like morphology and average particle size of 36 nm could be applied as an effective and magnetically recyclable catalyst without any significant decreasing of activity. Furthermore, the synergic effect of bimetallic Lewis acids was studied for the synthesis of imidazole derivatives.
A new magnetic hybrid, ZnS‐ZnFe2O4 MTMO, was designed, identified and used as an efficient heterogeneous nanocatalyst by a simple procedure for the synthesis of 2,4,5‐triaryl‐1H‐imidazoles.
In the last decade, isocyanide‐based multicomponent reactions, like the Passerini three‐component reaction (P‐3CR), have gained significant interest in the synthesis of sequence‐defined ...macromolecules due to their high efficiency and straightforward one‐pot procedures. The P‐3CR results in unique product structures that are particularly interesting for the synthesis of uniform, branched macromolecules, as they enable the direct introduction of a new branching point into the molecule. In this work, the synthesis of uniform first‐generation dendrons is performed via the P‐3CR using a divergent approach, utilizing three uniform and poorly soluble oligo(phenylene ethynylene)s (OPEs) of varying lengths as a focal moiety. Self‐assembly of the dendrons in cyclohexane solution is confirmed by fluorescence spectroscopy and diffusion‐ordered NMR (DOSY NMR) spectroscopy, highlighting the utility of DOSY NMR spectroscopy for the investigation of solution self‐assembly. Diffusion coefficients for the dendrons and their aggregates are determined and compared for different lengths of the OPE focal moiety. The successful synthesis of the dendrons in good yields and the selective branching introduced on the OPEs by the P‐3CR emphasize the high efficiency and synthetic advantages of multicomponent reactions for the preparation of uniform, branched macromolecules.
Uniform dendrons are synthesized in good yields using uniform rod‐like oligo(phenylene ethynylene)s of different lengths as poorly soluble focal units. The Passerini three‐component reaction is utilized to introduce branching. Self‐assembly of the dendrons in cyclohexane solution is investigated via fluorescence spectroscopy and diffusion‐ordered NMR spectroscopy.
