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1.
Org Biomol Chem ; 13(25): 6931-4, 2015 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-26035333

RESUMO

A copper(II)-catalyzed cyclization reaction of N-(2-alkynylphenyl)imine was developed. This strategy provided an effective procedure for the synthesis of substituted N-vinylindoles in moderate to good yields.


Assuntos
Cobre/química , Iminas/química , Indóis/síntese química , Alcenos/síntese química , Alcenos/química , Alcinos/síntese química , Alcinos/química , Catálise , Ciclização , Iminas/síntese química , Indóis/química
2.
Dalton Trans ; 53(5): 2055-2064, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38179885

RESUMO

The development prospects of conventional Li-ion batteries are limited by the paucity of Li resources. Mg-Li hybrid batteries (MLIBs) combine the advantages of Li-ion batteries and magnesium batteries. Li+ can migrate rapidly in the cathode materials, and the Mg anode has the advantage of being dendrite-free. In this study, a type of Li4Ti5O12 composite material doped with Sn4+ and a conductive carbon skeleton (Li4Ti4.9Sn0.1O12/C, Sn0.1-LTO/C) was prepared by a simple one-pot sol-gel method. The doped Sn4+ replaces part of Ti4+ in the crystal lattice, which makes Ti3+ require charge compensation, thus improving the ionic conductivity. The intervention of the conductive carbon skeleton further improves the conductivity of the Sn0.1-LTO/C composite material. The performance of Sn0.1-LTO/C as the cathode of MLIBs is explored. The initial discharge capacity was 159.1 mA h g-1 at 0.5 C, and it was maintained at 105 mA h g-1 even after 500 cycles. The excellent electrochemical performance is attributed to a small amount of Sn doping and the involvement of the conductive carbon skeleton, which indicated that the Sn0.1-LTO/C composite material provides great potential application in MLIBs.

3.
Front Chem ; 11: 1189866, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37324563

RESUMO

The hunt for a higher power storage, relatively inexpensive, non-polluting battery technology is currently a pressing issue because of the rapid growth of the worldwide economic and the progressively significant environmental pollution. Among the possible nanomaterials for rechargeable batteries that can have heteroatoms applied to it in order to improve its electrochemical behavior is LixTiy(PO4)3. Carbon-coated Mn-doped Li2Mn0.1Ti1.9(PO4)3 materials was synthesized by spray drying method. The material was characterized by XRD, SEM, TEM, BET, TGA et al. Crystal data refinement results by Rietveld method showed that the symmetry space group is Pbcn.The lattice parameters of Li2Mn0.1Ti1.9(PO4)3 are a = 11.9372 Å, b = 8.5409 Å, c = 8.5979 Å, α = ß = γ = 90°, V = 876.59 Å3 and Z = 4). Rietveld refinement was performed, and the confidence factors are Rwp = 11.79%, Rp = 9.14%, and χ2 = 1.425. It was exhibited that LMTP0.1/CA-700 material has good crystallinity. Testing the cells with LAND test procedure (200 mA/g current density for 200 cycles), the LMTP0.1/CA-700 material has a discharge specific capacity of about 65 mAh/g. The capacity decayed by only 3% during the cycle. It has some potential application values as cathode of lithium ion battery in the future.

4.
Data Brief ; 31: 105871, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32642507

RESUMO

The data presented in this manuscript showed the effects of the sodium sources on the morphology, crystallite size and carbon content of NaTi2(PO4)3/C composite obtained after heat treatment under N2 atmosphere of the as-spraydried powders. The morphology, crystalline size and carbon content of three products with different sodium sources were investigated. The data are related to "Synthesis of NaTi2(PO4)3@C microspheres by an in situ process and their electrochemical properties" (Mao et al.,2020).

5.
Data Brief ; 23: 103624, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30793015

RESUMO

The oxidation of amines to imines is an important chemical transformation. In this article, we report original data on the synthesis of carbon doped WO3-x ultrathin nanosheets via an acid-assisted one-pot process, which exhibit excellent photocatalytic activity in the aerobic oxidation of amines to corresponding imines under visible light irradiation at room temperature. The composition, microstructure, morphology, photocatalytic activity of the corresponding samples and possible mechanism are included here. The data are related to "Oxide Defect Engineering Enables to Couple Solar Energy into Oxygen Activation" (Zhang et al., 2016).

6.
Org Lett ; 18(5): 1064-7, 2016 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-26878938

RESUMO

A rhodium-catalyzed/copper-mediated tandem C(sp(2))-H alkynylation and intramolecular annulation of 2H-[1,2'-bipyridin]-2-ones with propargyl alcohols for the synthesis of 11-acylated imidazo[1,2-a:3,4-a']dipyridin-5-ium-4-olates is described.

7.
J Chromatogr Sci ; 52(7): 624-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23825350

RESUMO

A novel and sensitive method was developed for the determination of residues of tiadinil and its metabolite, 4-methyl-l,2,3-thiadiazole-5-carboxylic acid, in flue-cured tobacco. The pesticides were extracted with acetone and purified by gel permeation chromatography and solid-phase extraction. Analysis was performed by ultra-performance liquid chromatography-tandem mass spectrometry in negative ionization mode. Two precursor-product ion transitions were monitored for both compounds in the multiple reaction monitoring mode. Quantification was conducted by using matrix-matched standard calibration. Recovery values of the proposed method for tiadinil ranged from 72.5 to 98.2%, with relative standard deviations ranging from 3.8 to 9.5%; recovery values for 4-methyl-l,2,3-thiadiazole-5-carboxylic acid ranged from 75.4 to 103.3% with RSDs ranging from 3.7 to 9.3%. The limit of quantification for both compounds was 0.01 mg/kg. This method is valuable for residual analysis, quality control and monitoring of tiadinil and its metabolite, 4-methyl-l,2,3-thiadiazole-5-carboxylic acid, in tobacco.

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