A series of benzofuran and benzo[]thiophen derivatives was synthesized via a transition-metal-free one-pot process at room temperature. This one-pot protocol enables the synthesis of compounds with high reaction efficiency, mild conditions, simple methods, and a wide-ranging substrate scope. Regioselective five-membered heterocycles were constructed in good-to-excellent yields.
View Article and Find Full Text PDFAn iodine-mediated one-pot synthesis of pyrrolo/indolo [1,2-]quinoxalines and quinazolin-4-one via utilizing epoxides as alkyl precursors under metal-free conditions has been described. Both 1-(2-aminophenyl)-pyrrole and 2-aminobenzamide could be applied to this protocol. A total of 33 desired products were obtained with moderate to good yields.
View Article and Find Full Text PDFTo address the issue of pipeline blockage caused by the formation of waxy deposits inside pipelines, hindering the flow of petroleum in the Shengli oilfield, eight new-style polyacrylic acid pour point depressants (PPD) for Shengli crude oil were prepared by maleic anhydride and ene monomers with different polar and aromatic pendant chains. The synthesized Pour Point Depressants were characterized by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), and polarizing optical microscopy (POM). The results were promising and demonstrated that any type of pour point depressant exhibited excellent performance on high-pour-point crude oil.
View Article and Find Full Text PDFThe oxidation of benzyl alcohols is an important reaction in organic synthesis. Traditional methods for benzyl alcohol oxidation have not been widely utilized due to the use of significant amounts of precious metals and environmentally unfriendly reagents. In recent years, electrocatalytic oxidation has gained significant attention, particularly electrochemical anodic oxidation, which offers a sustainable alternative for oxidation without the need for external oxidants or reducing agents.
View Article and Find Full Text PDFHerein, we develop a base-promoted regioselective synthesis of -vinyl pyrazoles from vinyl sulfonium salts with diazo compounds. This metal-free synthetic protocol provides an efficient and practical approach to diverse -vinyl pyrazoles in good to excellent yields under mild conditions. The reaction appears to experience a [3 + 2] annulation of vinyl sulfonium salts and diazo anions rather than diazo compounds, followed by -vinylation.
View Article and Find Full Text PDFElectrochemically converting nitrate ions back to ammonia can not only eliminate water pollution but also obtain valuable ammonia without a serious carbon footprint, and is thus deemed as an efficient supplement to the traditional Haber-Bosch process. Currently reported catalysts can achieve a single electrode reaction in the electrochemical nitrate reduction reaction. However, the bifunctionality of a single catalyst for both cathodic and anodic reactions has not yet been reported.
View Article and Find Full Text PDFThe efficient "One-pot" CuCl-catalyzed C-S bond coupling reactions were developed for the synthesis of dibenzo[,][1,4]thiazepines and 11-methy-ldibenzo[,][1,4]thiazepines via 2-iodobenzaldehydes/2-iodoacetophenones with 2-aminobenzenethiols/2,2'-disulfanediyldianilines by using bifunctional-reagent N, N'-dimethylethane-1,2-diamine (DMEDA), which worked as ligand and reductant. The reactions were compatible with a range of substrates to give the corresponding products in moderate to excellent yields.
View Article and Find Full Text PDFThe selective oxidation of amines into imines is a priority research topic in organic synthesis and has attracted much attention over the past few decades. However, the oxidation of amines generally suffers from the drawback of transition-metal, even noble-metal catalysts. Thus, the strategy of metal- and oxidant-free selective synthesis of imines is highly desirable yet largely unmet.
View Article and Find Full Text PDFIn this study, low-temperature catalytic NO oxidation with HO over Na- and H-exchanged Y and ZSM-5 zeolites was investigated at 140 °C which is the average exhaust temperature of coal-fired power plant. Fast catalytic NO oxidation rates were observed over H-zeolites, and catalytic activity was proportional to the amount of Brønsted acid sites. HZSM-5 and HY zeolites show 65% and 95% NO removal efficiency, respectively, but the catalytic stability of HY was lower than HZM-5 due to partial dealumination during the reaction.
View Article and Find Full Text PDFConsidering that the utilization of fly ash in the removal of flue gas pollutants not only provide a way of high value-added utilization of fly ash, but also greatly reduce the cost of removing flue gas pollutant, the synthesis of silica sulfuric acid catalyst from fly ash and its application in simultaneous removal of NOx and SO with HO were investigated in this work. Circulating fluidized bed boiler (CFB) fly ash and pulverized coal boiler (PC) fly ash were selected as raw material to prepare silica sulfuric acid catalyst by HSO activation. PC fly ash was difficult to be activated by HSO due to its dense structure, while CFB fly ash could be treated with HSO to promote dealumination, thereby increasing the silica content.
View Article and Find Full Text PDFA novel banana-shaped molecule using 2,8-Dimethyl-6,12-5,11-methanodibenzo [] [1,5]diazocine (Tröger's base) as bent-core was synthesized via double Carbon-Carbon cross-coupling reaction. The double Sonogashira cross-coupling reaction was optimized by using Pd(PPh₃)₂Cl₂ as catalyst, CuI as cocatalyst and diisopropylamine as base in place of triethylamine. The structure of this compound was confirmed by ¹H-NMR, C-NMR, Fourier transform infrared (FT-IR) spectroscopy and mass spectrometry.
View Article and Find Full Text PDFA series of bibenzo[ b][1,4]thiazines with various functional groups has been synthesized by a free-radical condensation reaction. Bibenzo[ b][1,4]thiazines were obtained in moderate to good yield (up to 85%) through a one-step reaction of readily available 2,2'-dithiodianiline and methyl aryl ketones with AIBN as radical initiator in HOAc. Bibenzo[ b][1,4]thiazines exhibit diversiform solid-state packing.
View Article and Find Full Text PDFTwo transition metal (Cu and Pd)-catalyzed C-S, C-N, and C-C bond cross-coupling reactions for the preparation of N-fused benzo[4,5]imidazo[2,1-b]thiazole derivatives were developed. A variety of 3-substituted and 2,3-disubstituted benzo[4,5]imidazo[2,1-b]thiazoles were efficiently and conveniently synthesized from the coupling reaction via trans-1,2-diiodoalkenes, 1H-benzo[d]imidazole-2-thiols, and halobenzenes in moderate to excellent yields.
View Article and Find Full Text PDFA series of 1,4-thiazepin-5(4H)-one derivatives were synthesized via a transition metal-free one-pot Smiles rearrangement process at room temperature. Regioselective seven-membered heterocycles were constructed in good to excellent yields. To gain an in-depth understanding of the S-N type Smiles rearrangement mechanism, a theoretical study was also performed by quantum chemistry calculations.
View Article and Find Full Text PDFA one-pot transition metal-free method for synthesizing benzo[4,5]imidazo[1,2-a]quinazoline and imidazo[1,2-a]quinazoline derivatives has been developed. The approach is widely applicable to 2-fluoro-, 2-chloro-, 2-bromo- and 2-nitro-substituted aryl aldehyde and ketone substrates. The fluorescence properties of target compounds were studied.
View Article and Find Full Text PDFA transition metal-free methodology for the synthesis of pyridazinopyrido[3,2-f][1,4]thiazepine-diones was studied. The construction of this tricyclic system went through a one-pot coupling/Smiles rearrangement/cyclization process. The high yields of pure products were obtained through simple recrystallization.
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